Do you pray compline? You should pray compline. If you do, you know part of this psalm well.
There’s a horrific grammatical construction in verse 14 that deserves a little above-the-fold commentary. In eo dum…simul is a laugh-out-loud way to say “when,” and even my inclination to the slavishly-literal can’t quite push me to translate it as “In that [time] when at once…” Where I come from, we just say Dum and move on.
Here’s a speculative defense of St. Jerome, both here and in all the other famous “wha…?” moments of the Vulgate. St. Jerome, the tradition tells us, traveled to Jerusalem to study Hebrew and consult manuscripts as part of his epic translation labor. I propose he learned actual psaltery tunes and that his Latin gymnastics are an attempt to meet the metrical demands of the traditional Hebrew chants.
Some people, including me as a young man, like to dump on the Vulgate for being trashy, later Latin, but tend to forget that St. Jerome was extremely, formally educated and knew Latin better than anyone alive today. God accused him of loving Cicero more than Himself! I don’t think his signature work is going to be riddled with crappy Latin, and you shouldn’t either. So there’s a fanciful hypothesis to explain the oddities of his Latin.
“In te, Domine, speravi” (Psalm 30)
 In finem. Psalmus David, pro extasi.
Unto the end. A Psalm of David, pro extasi.
 In te, Domine, speravi; non confundar in aeternum; in justitia tua libera me.
In You, O Lord, have I hoped; I shall not be confounded into the eternal; in Your justice free me.
 Inclina ad me aurem tuam; accelera ut eruas me. Esto mihi in Deum protectorem, et in domum refugii, ut salvum me facias :
Incline to me Your ear; make haste that You may rescue me. Be for me unto a God protector and unto a house of refuge, that You may make me safe.
 quoniam fortitudo mea et refugium meum es tu; et propter nomen tuum deduces me et enutries me.
For my strength and my refuge You are; and on account of Your name You will lead me and nourish me.
 Educes me de laqueo hoc quem absconderunt mihi, quoniam tu es protector meus.
You will lead me from the snare here which they have hidden for me, for You are my protector.
 In manus tuas commendo spiritum meum; redemisti me, Domine Deus veritatis.
Into Your hands I commend my spirit; You have redeemed me, Lord God of truth.
 Odisti observantes vanitates supervacue; ego autem in Domino speravi.
You have hated those observing vanities emptily; whereas I have hoped in the Lord.
Exsultabo, et laetabor in misericordia tua, quoniam respexisti humilitatem meam; salvasti de necessitatibus animam meam.
I shall exult and be glad in Your mercy, for You have regarded my humility; You have saved my soul from necessities.
 Nec conclusisti me in manibus inimici; statuisti in loco spatioso pedes meos.
Nor have You shut me up in the hands of enemies; You have stood my feet in a spacious place.
 Miserere mei, Domine, quoniam tribulor; conturbatus est in ira oculus meus, anima mea, et venter meus.
Have mercy on me, O Lord, for I am troubled; disturbed in wrath is my eye, my soul, and my belly.
 Quoniam defecit in dolore vita mea, et anni mei in gemitibus. Infirmata est in paupertate virtus mea; et ossa mea conturbata sunt.
For my life fails in sorrow, and my years in weepings. Infirm in poverty is my might, and my bones are troubled.
 Super omnes inimicos meos factus sum opprobrium, et vicinis meis valde, et timor notis meis; qui videbant me foras fugerunt a me.
Over all my enemies I am made a reproach, and by my neighbors loudly, and fear in my features; who used to see me abroad have fled from me.
 Oblivioni datus sum, tamquam mortuus a corde. Factus sum tamquam vas perditum;
I am given to oblivion, like a man dead from the heart. I am made like a vessel destroyed;
 quoniam audivi vituperationem multorum commorantium in circuitu. In eo dum convenirent simul adversum me, accipere animam meam consiliati sunt.
for I have heard the condemnation of many tarrying round about. When* they gather at once against me, to seize my soul have they taken counsel.
 Ego autem in te speravi, Domine; dixi : Deus meus es tu;
I, however, I have hoped in You O Lord; I have said, “My God are You.
 in manibus tuis sortes meae : eripe me de manu inimicorum meorum, et a persequentibus me.
in Your hands are my lots; rescue me from the hand of my enemies, and from those pursuing me.”
 Illustra faciem tuam super servum tuum; salvum me fac in misericordia tua.
Shine Your face over Your servant; make me safe in Your mercy.
 Domine, non confundar, quoniam invocavi te. Erubescant impii, et deducantur in infernum;
O Lord, I shall not be confounded, for I have called upon You. Let them be put to shame, the impious, and let them be led into hell;
 muta fiant labia dolosa, quae loquuntur adversus justum iniquitatem, in superbia, et in abusione.
Let them be mute, the sorrowful lips which speak injustice against the just in pride and in abuse.
 Quam magna multitudo dulcedinis tuae, Domine, quam abscondisti timentibus te! Perfecisti eis qui sperant in te, in conspectu filiorum hominum.
How great the multitude of Your sweetness, O Lord, which You have hidden for those fearing You! You have accomplished for them who hope in You, in the sight of the sons of men.
 Abscondes eos in abscondito faciei tuae, a conturbatione hominum; proteges eos in tabernaculo tuo, a contradictione linguarum.
You will hide them in the hiding place of Your face, from the tumult of men; You will protect them in Your tabernacle, from the accusation of tongues.
 Benedictus Dominus, quoniam mirificavit misericordiam suam mihi in civitate munita.
Blessed Lord, for He has made wonderful His mercy to me in the fortified city.
 Ego autem dixi in excessu mentis meae : Projectus sum a facie oculorum tuorum : ideo exaudisti vocem orationis meae, dum clamarem ad te.
I myself have said in the withdrawal of my mind, “I am hurled from the face of Your eyes;” and so You have heard the voice of my prayer when I cried to You.
 Diligite Dominum, omnes sancti ejus, quoniam veritatem requiret Dominus, et retribuet abundanter facientibus superbiam.
Rejoice in the Lord, all ye His holy ones, for truth does the Lord seek, and He repays abundantly those working pride.
 Viriliter agite, et confortetur cor vestrum, omnes qui speratis in Domino.
Manfully act, and let your heart be comforted, all who hope in the Lord.
pro extasi means something like for a trance, possibly in the sense of meditation. I’ve left it in Latin on the assumption that it names a form or style of music.