Psalm 118 (Beth) - (Sunday Prime no 2)

Painting by Jean Weyh in the St Stephen's church of Mackenheim, France

Psalm 118, Beth (Vs 9-16): In quo corrigit 

Vulgate	Douay-Rheims
9. In quo córrigit adolescéntior viam suam? * in custodiéndo sermónes tuos.	By what does a young man correct his way? By observing your words
10. In toto corde meo exquisívi te: * ne repéllas me a mandátis tuis.	With my whole heart have I sought after you: let me not stray from your commandments.
11  In corde meo abscóndi elóquia tua: * ut non peccem tibi.	Your words have I hidden in my heart, that I may not sin against you
12. Benedíctus es, Dómine: * doce me justificatiónes tuas.	Blessed are you, O Lord: teach me your justifications.
13  In lábiis meis, * pronuntiávi ómnia judícia oris tui.	With my lips I have pronounced all the judgments of your mouth.
14  In via testimoniórum tuórum delectátus sum, * sicut in ómnibus divítiis.	I have been delighted in the way of your testimonies, as much as in all riches.
15  In mandátis tuis exercébor: * et considerábo vias tuas.	I will meditate on your commandments: and I will consider your ways.
16 In justificatiónibus tuis meditábor: * non oblivíscar sermónes tuos.	I will think of your justifications: I will not forget your words.

You can hear the verse read aloud in Latin here.

This octave of verses starts by talking about the importance of starting out on the right path as a young person, and ends with a rejection of ‘forgetfulness’, or falling away from God. Taken together, they are, I think, a prayer for the grace of perseverance.

Beth is the second psalm of Sunday Prime, and essentially has the same message as the second psalm of Monday Prime (Psalm 2), namely the call for us to take refuge in God, and submit to his discipline.   This portion of Psalm 118 urges us to start young, listen carefully to what God is saying, and remember them always by the practice of meditation.  In short, conversion takes effort.

Cassiodorus:

In the section of the first letter, the faithful people pointed to the spheres of blessedness in which they begged to be maintained; they now under the second letter reveal the time of conversion, and by quoting the Lord's words also state what delights they are to enjoy.

Fr Pasch:

Serve God with all your strength

You can read more on these verses of Psalm 118 here.

Psalm 18 (Saturday Prime no 2)

Mausoleum of the Julii,  necropolis under St. Peter's
Mid-3rd century Grotte Vaticane, Rome.

Saturday – Psalm 18 (19): Caeli enarrent gloriam Dei 

Vulgate	Douay-Rheims
In finem. Psalmus David.	Unto the end. A psalm for David.
Cæli enárrant glóriam Dei: * et ópera mánuum ejus annúntiat firmaméntum.	The heavens show forth the glory of God, and the firmament declares the work of his hands.
2  Dies diéi erúctat verbum, * et nox nocti índicat sciéntiam.	Day to day utters speech, and night to night shows knowledge.
3  Non sunt loquélæ, neque sermónes, * quorum non audiántur voces eórum.	There are no speeches nor languages, where their voices are not heard.
4  In omnem terram exívit sonus eórum: * et in fines orbis terræ verba eórum.	Their sound has gone forth into all the earth: and their words unto the ends of the world.
5  In sole pósuit tabernáculum suum: * et ipse tamquam sponsus procédens de thálamo suo.	He has set his tabernacle in the sun: and he as a bridegroom coming out of his bridechamber,
6  Exsultávit ut gigas ad curréndam viam, * a summo cælo egréssio ejus.	Has rejoiced as a giant to run the way: His going out is from the end of heaven,
7  Et occúrsus ejus usque ad summum ejus: * nec est qui se abscóndat a calóre ejus.	And his circuit even to the end thereof: and there is no one that can hide himself from his heat.
8  Lex Dómini immaculáta, convértens ánimas: * testimónium Dómini fidéle, sapiéntiam præstans párvulis.	The law of the Lord is unspotted, converting souls: the testimony of the Lord is faithful, giving wisdom to little ones.
9  Justítiæ Dómini rectæ, lætificántes corda: * præcéptum Dómini lúcidum illúminans óculos.	The justices of the Lord are right, rejoicing hearts: the commandment of the Lord is lightsome, enlightening the eyes.
10  Timor Dómini sanctus, pérmanens in sæculum sæculi: * judícia Dómini vera, justificáta in semetípsa.	The fear of the Lord is holy, enduring for ever and ever: the judgments of the Lord are true, justified in themselves.
11  Desiderabília super aurum et lápidem pretiósum multum: * et dulcióra super mel et favum.	More to be desired than gold and many precious stones: and sweeter than honey and the honeycomb.
12  Etenim servus tuus custódit ea, * in custodiéndis illis retribútio multa.	For your servant keeps them, and in keeping them there is a great reward.
13  Delícta quis intélligit? ab occúltis meis munda me: * et ab aliénis parce servo tuo.	Who can understand sins? From my secret ones cleanse me, O Lord: And from those of others spare your servant.
14  Si mei non fúerint domináti, tunc immaculátus ero: * et emundábor a delícto máximo	If they shall have no dominion over me, then shall I be without spot: and I shall be cleansed from the greatest sin.
15  Et erunt ut compláceant elóquia oris mei: * et meditátio cordis mei in conspéctu tuo semper.	And the words of my mouth shall be such as may please: and the meditation of my heart always in your sight.
16  Dómine, adjútor meus, * et redémptor meus.	O Lord, my helper and my Redeemer.

(Note: Uses classical pronunciation on 'ti' - ecclesiastical practice is to make it 'si'.)


Theodoret of Cyr

We learn three kinds of divine laws from blessed Paul. One unwritten kind he said was given to human beings in creation and nature: "From the creation of the world," he says, "his invisible attributes have been understood and seen in created things"; and again, "For when the Gentiles, who do not have the law, practice the obligations of the law instinctively, despite having no law they are a law to themselves." ... Another law was provided in writing through the mighty Moses: "The Law was added because of transgressions," he says, "ordained through angels in the hand of a mediator." He knew also a third one imposed after these, the law of grace: "For the law of the Spirit of life," he says, "has set me free from the law of sin and death.” Blessed David in this psalm teaches in beings the harmony between these, following the same order: first, the one the Creator in creation; then the one given through Moses, instilling a greater knowledge of the Creator to those willing to attend; after that, in law of grace, perfectly purifying souls and saving them from the present destruction. This is in fact the reason the psalm also refers us "to the end," naming the New Testament in the end. Commentary on the Psalms

St John Chrysostom:

The mystical interpretation of this Psalm here indicated, is acknowledged by the Church in using it on Christmas day. An ancient Latin hymn has this paraphrase on a part of it:

From Chastity, His Palace bright, Forth came the Bridegroom decked with light, Giant! God and Man in one! Glad His glorious race to run. From the Eternal Father sent Back to Him His circuit bent, Down to hell His path descends, At the throne of God it ends

St Alphonse Liguori

In this psalm we hear exalted the perfections of God, the sanctity of his law, and the magnificence of his works. In the spiritual sense it is to Jesus Christ and his Apostles that all these praises apply, according to St. Augustine, Bellarmine, Rotigni, Malvenda, Tirinus, and Gordona.

Fr Pasch:

This is the famous sun Psalm.  More beautifully than all the rest of creation, the sun proclaims the glory of God; in fact the sun is the symbol of God, the symbol of Christ.  In the second part, the Psalm is a song of praise for the spiritual sun, the Law of God.  In this Psalm, the Church has also seen a figure of the Incarnation of Christ in the womb of the Virgin Mother; Mary is the tabernacle of the divine Sun, who comes out from this tabernacle on Christmas night like a bridegroom, like a mighty hero

NT References: Rom 1:20 (v3), Rom 10:18(v4), Jas 1:25 (v9); Rev 16:7(vs 10), Rom 6:12, 14(v13)

RB cursus	Saturday Prime
Monastic/(Roman) feasts etc	Comon of Apostles, Virgins/Holy Women, Nativity, Ascension, Pentecost, Trinity, Assumption
Roman pre 1911	Sunday Matins
Ambrosian	Matins Tues wk 1
Brigittine	Saturday matins
Maurist	Saturday Prime
Thesauris	Schema B: Wednesday matins;
Roman post 1911	1911-62:Monday Prime  1970: Lauds Monday wk 2 (18a)/Midday wk I (18b)
Mass propers (EF)	Lent 2 Sat IN (1, 8); Lent 3 Sunday OF (9, 11, 12); Lent 3 Tues Gr (13-14); Lent 4 Monday CO (13), Lent 4 Friday In (1, 15); Vigil JB IN (1).

Psalm 16 (Friday Prime no 2)

Walters Ms. W.721, Book of Hours, fol. 86v, c1450
Offices for Each Day of the Week, Friday: Cross
Digitilised Walter Manuscripts

Psalm 16 (17): Exaudi Domine justitiam meam 

Vulgate	Douay-Rheims
Oratio David	The prayer of David.
Exáudi, Dómine, justítiam meam: * inténde deprecatiónem meam.	Hear, O Lord, my justice: attend to my supplication.
2  Auribus pércipe oratiónem meam, * non in lábiis dolósis.	Give ear unto my prayer, which proceeds not from deceitful lips.
3   De vultu tuo judícium meum pródeat: * óculi tui vídeant æquitátes	Let my judgment come forth from your countenance: let your eyes behold the things that are equitable.
4  Probásti cor meum, et visitásti nocte: * igne me examinásti, et non est invénta in me iníquitas.	You have proved my heart, and visited it by night, you have tried me by fire: and iniquity has not been found in me.
5  Ut non loquátur os meum ópera hóminum: * propter verba labiórum tuórum ego custodívi vias duras.	That my mouth may not speak the works of men: for the sake of the words of your lips, I have kept hard ways
6  Pérfice gressus meos in sémitis tuis: * ut non moveántur vestígia mea.	Perfect my goings in your paths: that my footsteps be not moved.
7  Ego clamávi, quóniam exaudísti me, Deus: * inclína aurem tuam mihi, et exáudi verba mea.	I have cried to you, for you, O God, have heard me: O incline your ear unto me, and hear my words.
8  Mirífica misericórdias tuas, * qui salvos facis sperántes in te.	Show forth your wonderful mercies; you who save them that trust in you.
9  A resisténtibus déxteræ tuæ custódi me, * ut pupíllam óculi.	From them that resist your right hand keep me, as the apple of your eye.
10  Sub umbra alárum tuárum prótege me: * a fácie impiórum qui me afflixérunt.	Protect me under the shadow of your wings. From the face of the wicked who have afflicted me.
11  Inimíci mei ánimam meam circumdedérunt, ádipem suum conclusérunt : * os eórum locútum est supérbiam.	My enemies have surrounded my soul: They have shut up their fat: their mouth has spoken proudly.
12  Projiciéntes me nunc circumdedérunt me: * óculos suos statuérunt declináre in terram.	They have cast me forth, and now they have surrounded me: they have set their eyes bowing down to the earth.
13  Suscepérunt me sicut leo parátus ad prædam: * et sicut cátulus leónis hábitans in ábditis.	They have taken me, as a lion prepared for the prey; and as a young lion dwelling in secret places.
14  Exsúrge, Dómine, prǽveni eum, et supplánta eum: * éripe ánimam meam ab ímpio, frámeam tuam ab inimícis manus tuæ.	Arise, O Lord, disappoint him and supplant him; deliver my soul from the wicked one; your sword from the enemies of your hand.
15  Dómine, a paucis de terra dívide eos in vita eórum: * de abscónditis tuis adimplétus est venter eórum.	O Lord, divide them from the few of the earth in their life: their belly is filled from your hidden stores.
16  Saturáti sunt fíliis: * et dimisérunt relíquias suas párvulis suis.	They are full of children: and they have left to their little ones the rest of their substance.
17  Ego autem in justítia apparébo conspéctui tuo: * satiabor cum apparúerit glória tua.	But as for me, I will appear before your sight in justice: I shall be satisfied when your glory shall appear.

Psalm 16 can be read as a meditation on the Passion, hence its particular appropriateness for Friday in the Benedictine Office. 

In the first part (verses 1-5) the speaker asks for justice in the face of persecution and suffering, since his cause is just and he is without sin.  Our Lord is of course the only person who can truly say these verses without reservation, yet through the grace given to us in the sacraments he instituted we too can claim to be justified in the sight of God.

In the second part (verses 7-13) he asks for help in standing firm in the face of the enemy – and St Thomas Aquinas interprets the reference to wings as a symbolic allusion to the two arms of Our Lord stretched out on the Cross.  Verses 10-13 are explicitly interpreted for us in Matthew 23, when Our Lord castigated the Pharisees for their unfortunate habit of killing the prophets God sends to them.

In the third part (verses 14-17) the speaker asks for justice and the punishment of the enemy.  Note though, that, according to the last verse, the justice asked for here is above all the revelation of the glory of God, revealed in the Resurrection.  

You can hear the psalm read aloud here.

St Augustine:

This prayer must be assigned to the Person of the Lord, with the addition of the Church, which is His body

St Robert Bellarmine:

This psalm arises from prayer because in the midst of tribulations, prayer is an unparalleled refuge; Psalm 108: "Instead of making me a return of love, they detracted me: but I gave myself to prayer." This psalm, then, is divided into two parts. In the first, he prays for his own endurance. In the second, he asks for deliverance from evil, at I have cried....

St Alphonsus Liguori:

The just man prays to God to be delivered from the persecutions to which he sees himself exposed. Motives of his confidence: his innocence and rectitude, the mercy and justice of God, the malice and iniquity of the wicked.

Fr Pasch:

Battle in the Kingdom - After seeing the lines drawn up, friend and foe, we see the battle itself.  Innocency and justice fight with sin.  It is a fierce struggle, but God is the mighty champion.  The temptations of the devil are vividly portrayed.  This is the Psalm that St. Lawrence prayed while he was being martyred.

Scriptural and liturgical uses of the psalm

NT references	1 Pet 1:7 (v4), Mt 23:37 (v11- the Lord upbraids the scribes and Pharisees and castigates the persecution of God’s prophets and saints), 1 Jn 3:2, Rev 22:4 (v17 – shall behold his face)
RB cursus	Friday Prime
Monastic/(Roman) feasts etc	-
Roman pre 1911	: Sunday matins
Roman post 1911	1911-62: Monday Matins . 1970:
Mass propers (EF)	Lent I Thurs, GR (3, 9); Lent wk II  Friday, IN (1, 17), Lent III, Tues, IN (1, 7, 9); PP 6 OF (6-8), PP 10 GR (3, 9)

Psalm 13 (Prime No 2, Thursday) - Overview** updated

BL Harley 1892, British Library

Psalm 13 is almost identical to Psalm 52, so by learning this one, you get two for the price of one.

The text of the psalm

Psalm 13 (14) - Dixit insípiens in corde suo  

Vulgate	Douay-Rheims
In finem. Psalmus David.	Unto the end, a psalm for David.
Dixit insípiens in corde suo: * Non est Deus.	The fool has said in his heart: There is no God.
2  Corrúpti sunt, et abominábiles facti sunt in stúdiis suis: * non est qui fáciat bonum, non est usque ad unum.	They are corrupt, and have become abominable in their ways: there is none that does good, no not one.
3  Dóminus de cælo prospéxit super fílios hóminum, * ut vídeat si est intélligens, aut requírens Deum.	The Lord has looked down from heaven upon the children of men, to see if there be any that understand and seek God.
4  Omnes declinavérunt, simul inútiles facti sunt: * non est qui fáciat bonum, non est usque ad unum.	They are all gone aside, they have become unprofitable together: there is none that does good: no not one.
a  Sepúlcrum patens est guttur eórum: linguis suis dolóse agébant * venénum áspidum sub lábiis eórum.(Ps 5:10)	Their throat is an open sepulchre; with their tongues they acted deceitfully: the poison of asps is under their lips.
b Quorum os maledictióne et amaritúdine plenum est: * velóces pedes eórum ad effundéndum sánguinem (Ps 10:7)	Their mouth is full of cursing and bitterness; their feet are swift to shed blood.
c  Contrítio et infelícitas in viis eórum, et viam pacis non cognovérunt: * non est timor Dei ante óculos eórum.](Is 59:7-8; Prov 1:16)	Destruction and unhappiness in their ways; and the way of peace they have not known: there is no fear of God before their eyes.
5  Nonne cognóscent omnes qui operántur iniquitátem, * qui dévorant plebem meam sicut escam panis?	Shall not all they know that work iniquity, who devour my people as they eat bread?
6  Dóminum non invocavérunt, * illic trepidavérunt timóre, ubi non erat timor.	They have not called upon the Lord: there have they trembled for fear, where there was no fear
7  Quóniam Dóminus in generatióne justa est, consílium ínopis confudístis: * quóniam Dóminus spes ejus est.	For the Lord is in the just generation: you have confounded the counsel of the poor man; but the Lord is his hope.
8  Quis dabit ex Sion salutáre Israël? * cum averterit Dóminus captivitátem plebis suæ, exsultábit Jacob, et lætábitur Israël.	Who shall give out of Sion the salvation of Israel? When the Lord shall have turned away the captivity of his people, Jacob shall rejoice, and Israel shall be glad.

You can hear it read aloud here but I'm afraid I haven't been able to locate any useful recordings of it being sung.

Traditional interpretations of the psalm

In Romans 3, St Paul cites this psalm (including a number of verses expunged from 1962 and onwards editions of the psalter, see below) as part of his explanation of the idea that no one can be saved by the (old) law alone, but only through Christ.

The title of this psalm in the Septuagint helps make the link: it is ‘to the end’, which the earliest commentators saw as pointing to its Christological application, for as St Paul says (Romans 10:4) ‘Christ is the end of the law’.  St Augustine, for example, commented:

For Christ is the end of the law for righteousness to every one that believes; Romans 10:4 as the Apostle says. We believe in Him, when we begin to enter on the good road: we shall see Him, when we shall get to the end. And therefore is He the end. For not even have certain sacrilegious and abominable philosophers, who entertain perverse and false notions of God, dared to say, There is no God.

The overall theme of the psalm is the corrupted state of man that flows from Original Sin, and is manifested in the malice and deceitfulness of those who oppose God – to the point of plotting to kill Our Lord.  St Athanasius, for example, suggested that:

When you hear people blaspheming against the providence of God, intercede with God with this psalm

Similarly St Alphonsus Liguori commented that:

The prophet deplores the blindness and the corruption of the wicked, and especially of infidels....

 Psalm 13 and 'interpolated' verses

I noted above that some verses of the psalm have been omitted in the 1962 and subsequent editions of the Monastic Diurnal  (and breviary).  I’ve included them in the table above, labeled a, b and c in italics.  They are all verses used elsewhere in Scripture, as I have noted), with a note of the original source of the citation).

The verses in question can be found in Romans 3:13-18 (as well as the approved Vulgate and Douay-Rheims translations), but were removed from monastic office in 1962, and subsequently from the neo-Vulgate text on the basis, as far as I can gather, that they aren't in the Hebrew 'original' and were just Christian interpolations of other texts.

Doubt about these verses is not new: St Jerome, for example, long ago advocated that they be removed from the psalter, but was overruled.

So why were they removed in 1962?

It may be it was just a matter of the fashion of the times, which tended to argue for the superiority of the the Hebrew Masoretic Text over the Septuagint-Vulgate tradition, and seek to expunge all the 'hard sayings' of Scripture.

There is however, perhaps one other explanation.

One of the other changes in the 1962 psalter was to move the opening verses of Wednesday Prime (the verses of Psalm 9 starting Exsurge Domine) to the end of Tuesday.  It is a change that doesn't make a lot of sense, first since the antiphon of the hour still reflects the old starting point, and secondly because the divisio point was clearly intended to resonate with several of the psalms of Matins on Wednesday (take a look at Psalms 67 and 68 in particular).

But the words 'Exsurge Domine' (albeit quoting Psalm 73) are the opening words of Pope Leo X's condemnation of the theses of Luther.  Moreover, it went on to cite those now expunged verses of Psalm 13. 

Could it be that these verses were deliberately de-emphasized and/or expunged from the Benedictine psalter because they were seen as offending ecumenical sensibilities?

Here are the opening paragraph's of Pope Leo X's Bull for your consideration:

Arise, O Lord, and judge your own cause. Remember your reproaches to those who are filled with foolishness all through the day. Listen to our prayers, for foxes have arisen seeking to destroy the vineyard whose winepress you alone have trod. When you were about to ascend to your Father, you committed the care, rule, and administration of the vineyard, an image of the triumphant church, to Peter, as the head and your vicar and his successors. The wild boar from the forest seeks to destroy it and every wild beast feeds upon it.

Rise, Peter, and fulfill this pastoral office divinely entrusted to you as mentioned above. Give heed to the cause of the holy Roman Church, mother of all churches and teacher of the faith, whom you by the order of God, have consecrated by your blood. Against the Roman Church, you warned, lying teachers are rising, introducing ruinous sects, and drawing upon themselves speedy doom. Their tongues are fire, a restless evil, full of deadly poison. They have bitter zeal, contention in their hearts, and boast and lie against the truth.

We beseech you also, Paul, to arise. It was you that enlightened and illuminated the Church by your doctrine and by a martyrdom like Peter's. For now a new Porphyry rises who, as the old once wrongfully assailed the holy apostles, now assails the holy pontiffs, our predecessors....

Rebuking them, in violation of your teaching, instead of imploring them, he is not ashamed to assail them, to tear at them, and when he despairs of his cause, to stoop to insults. He is like the heretics "whose last defense," as Jerome says, "is to start spewing out a serpent's venom with their tongue when they see that their causes are about to be condemned, and spring to insults when they see they are vanquished." For although you have said that there must be heresies to test the faithful, still they must be destroyed at their very birth by your intercession and help, so they do not grow or wax strong like your wolves. Finally, let the whole church of the saints and the rest of the universal church arise. Some, putting aside her true interpretation of Sacred Scripture, are blinded in mind by the father of lies. Wise in their own eyes, according to the ancient practice of heretics, they interpret these same Scriptures otherwise than the Holy Spirit demands, inspired only by their own sense of ambition, and for the sake of popular acclaim, as the Apostle declares. In fact, they twist and adulterate the Scriptures. As a result, according to Jerome, "It is no longer the Gospel of Christ, but a man's, or what is worse, the devil's."

Let all this holy Church of God, I say, arise, and with the blessed apostles intercede with almighty God to purge the errors of His sheep, to banish all heresies from the lands of the faithful, and be pleased to maintain the peace and unity of His holy Church.

Scriptural and liturgical uses of the psalm 

NT references	Tit 1:16 (v2); Rom 3:11-18; Rom 11:26 (v8)
RB cursus	Thursday Prime
Monastic/(Roman) feasts etc	-
Roman pre 1911	Sunday Matins
Roman post 1911	1911-62: Monday Matins . 1970:
Mass propers (EF)	Lent 3, Monday, CO (8)

Psalm 10 (Wednesday Prime No 2) - Summary

c12th Passionary of Weissenau, Cod. Bodmer 127, fol. 103r.

Psalm 10: In Domino confido

Vulgate	Douay-Rheims
In finem. Psalmus David.	Unto the end. A psalm to David.
In Dómino confído : quómodo dícitis ánimæ meæ: * Tránsmigra in montem sicut passer?	In the Lord I put my trust: how then do you say to my soul: Get you away from hence to the mountain, like a sparrow.
2  Quóniam ecce peccatóres intendérunt arcum, paravérunt sagíttas suas in pháretra, * ut sagíttent in obscúro rectos corde.	For, lo, the wicked have bent their bow: they have prepared their arrows in the quiver, to shoot in the dark the upright of heart.
3  Quóniam quæ perfecísti, destruxérunt: * justus autem quid fecit?	For they have destroyed the things which you have made: but what has the just man done
4  Dóminus in templo sancto suo, * Dóminus in cælo sedes ejus.	The Lord is in his holy temple, the Lord's throne is in heaven
5  Oculi ejus in páuperem respíciunt: * pálpebræ ejus intérrogant fílios hóminum.	His eyes look on the poor man: his eyelids examine the sons of men
6  Dóminus intérrogat justum et ímpium: * qui autem díligit iniquitátem, odit ánimam suam.	The Lord tries the just and the wicked: but he that loves iniquity, hates his own soul
7  Pluet super peccatóres láqueos: * ignis, et sulphur, et spíritus procellárum pars cálicis eórum.	He shall rain snares upon sinners: fire and brimstone, and storms of winds, shall be the portion of their cup.
8  Quóniam justus Dóminus, et justítias diléxit: * æquitátem vidit vultus ejus.	For the Lord is just, and has loved justice: his countenance has beheld righteousness.

St Benedict makes Wednesday as a fast day in his Rule, consistent with the early Christian practice and association of the day with Judas’ betrayal.  In this context Psalm 10 can be read as a call to spiritual heroism in imitation of Christ as he faced his coming Passion, and a reminder that though evil seems at times to triumph, ultimately justice will prevail (indeed Pope St John Paul II’s catechesis on the psalm pointed to the reference to fire and brimstone as a reminder of the fate of the city of Sodom).

The original historical context for this psalm is probably David’s time at the court of mad King Saul, when he was constantly under suspicion, and was in fact forced to flee and live in the caves in the mountainous regions several times during this period.  On this particular occasion, however, although anxious friends concerned about his safety urge him to flee, he rejects the advice, confident that God wishes him to stay.  The first two verses have an obvious Christological application as we ponder the events of Wednesday in Holy Week in today's Office, for they warn that ‘unless you flee, they will kill you’.  Yet Our Lord, knowing the coming betrayal he faced, chose not to flee, not to shirk the cup.

The psalm is also, though, a commentary on the corrupt state of a society in turmoil.  The Fathers and Theologians accordingly read it as being primarily about the threat posed by heresy.   

St Augustine:

Appears to be sung against the heretics, who, by rehearsing and exaggerating the sins of many in the Church, as if either all or the majority among themselves were righteous, strive to turn and snatch us away from the breasts of the one True Mother Church... let him refer the Psalm to the Lord's passion, and of the Jews say, For they have destroyed what You have perfected; and of the Lord Himself, But what has the Just done? whom they accused as the destroyer of the Law: whose precepts, by their corrupt living, and by despising them, and by setting up their own, they had destroyed, so that the Lord Himself may speak as Man, as He is wont, saying, In the Lord I trust; how say ye to my soul, Remove into the mountains as a sparrow? by reason, that is, of the fear of those who desire to apprehend and crucify Him.

 St Thomas Aquinas:

This psalm can be explained literally of David, or mystically of Christ, or allegorically. Morally it concerns the just man, and heretics. The title (of this psalm is) Unto the end. A psalm for David. Jerome('s version) has Conqueror. In the preceding psalm, the giving of thanks was set forth for (the psalmist's) liberation from (his) enemies. Here, he shows the confidence brought about by having received (this liberation). And he speaks from the stance of one desiring God's kindnesses which follows upon freedom from danger. 

St Alphonse Liguori:

In this psalm the just are exhorted to place confidence in God during the time of persecution.

Fr Pasch:

This song of David forms a logical extension and climax to the previous Psalm.  "In God is my trust" - that is the shield for God's citizen in every crisis.

Pope St John Paul II:

The spiritual key of the entire psalm is well-expressed in the concluding verse:  "For the Lord is just, he loves just deeds". This is the root of all trust and the source of all hope on the day of darkness and trial. God is not indifferent to right and wrong:  he is a good God and not a dark, incomprehensible, mysterious destiny.  The psalm unfolds substantially in two scenes: in the first (cf. vv. 1-3), the wicked man is described in his apparent victory... the turning point comes...in the second scene (cf. vv. 4-7). The Lord, seated on the heavenly throne, takes in the entire human horizon with his penetrating gaze. From that transcendent vantage point, sign of the divine omniscience and omnipotence, God is able to search out and examine every person, distinguishing the righteous from the wicked and forcefully condemning injustice (cf. vv. 4-5). 

Scriptural and liturgical uses of the psalm

NT references	Mt 5:34(v4); Rev 8:5, 14:10, 20:10 (v7); Mt 5:8 (v8)
RB cursus	Prime Wednesday
Monastic/(Roman) feasts etc	Martyrs, Confessors, Dedication of a Church; Ascension, Holy Cross
Roman pre 1911	Sunday Matins
Roman post 1911	1911-62: Sunday Matins . 1970:
Mass propers (EF)	Lent 2 Wednesday (v8)