Allegri Miserere

This translation is from the 1662 Book of Common Prayer, and is used in Ivor Atkins' English edition of the Miserere (published by Novello):

Have mercy upon me, O God, after Thy great goodness
According to the multitude of Thy mercies do away mine offences.
Wash me thoroughly from my wickedness: and cleanse me from my sin.
For I acknowledge my faults: and my sin is ever before me.
Against Thee only have I sinned, and done this evil in thy sight: that Thou mightest be justified in Thy saying, and clear when Thou art judged.
Behold, I was shapen in wickedness: and in sin hath my mother conceived me.
But lo, Thou requirest truth in the inward parts: and shalt make me to understand wisdom secretly.
Thou shalt purge me with hyssop, and I shall be clean: Thou shalt wash me, and I shall be whiter than snow.
Thou shalt make me hear of joy and gladness: that the bones which Thou hast broken may rejoice.
Turn Thy face from my sins: and put out all my misdeeds.
Make me a clean heart, O God: and renew a right spirit within me.
Cast me not away from Thy presence: and take not Thy Holy Spirit from me.
O give me the comfort of Thy help again: and stablish me with Thy free Spirit.
Then shall I teach Thy ways unto the wicked: and sinners shall be converted unto Thee.
Deliver me from blood-guiltiness, O God, Thou that art the God of my health: and my tongue shall sing of Thy righteousness.
Thou shalt open my lips, O Lord: and my mouth shall shew Thy praise.
For Thou desirest no sacrifice, else would I give it Thee: but Thou delightest not in burnt-offerings.
The sacrifice of God is a troubled spirit: a broken and contrite heart, O God, shalt Thou not despise.
O be favourable and gracious unto Sion: build Thou the walls of Jerusalem.
Then shalt Thou be pleased with the sacrifice of righteousness, with the burnt-offerings and oblations: then shall they offer young calves upon Thine altar.
Psalm 51

the Latin found on .wikipedia.

 The original is written in Latin:

Miserere mei, Deus: secundum magnam misericordiam tuam.
Et secundum multitudinem miserationum tuarum, dele iniquitatem meam.
Amplius lava me ab iniquitate mea: et a peccato meo munda me.
Quoniam iniquitatem meam ego cognosco: et peccatum meum contra me est semper.
Tibi soli peccavi, et malum coram te feci: ut justificeris in sermonibus tuis, et vincas cum judicaris.
Ecce enim in iniquitatibus conceptus sum: et in peccatis concepit me mater mea.
Ecce enim veritatem dilexisti: incerta et occulta sapientiae tuae manifestasti mihi.
Asperges me hysopo, et mundabor: lavabis me, et super nivem dealbabor.
Auditui meo dabis gaudium et laetitiam: et exsultabunt ossa humiliata.
Averte faciem tuam a peccatis meis: et omnes iniquitates meas dele.
Cor mundum crea in me, Deus: et spiritum rectum innova in visceribus meis.
Ne proiicias me a facie tua: et spiritum sanctum tuum ne auferas a me.
Redde mihi laetitiam salutaris tui: et spiritu principali confirma me.
Docebo iniquos vias tuas: et impii ad te convertentur.
Libera me de sanguinibus, Deus, Deus salutis meae: et exsultabit lingua mea justitiam tuam.
Domine, labia mea aperies: et os meum annuntiabit laudem tuam.
Quoniam si voluisses sacrificium, dedissem utique: holocaustis non delectaberis.
Sacrificium Deo spiritus contribulatus: cor contritum, et humiliatum, Deus, non despicies.
Benigne fac, Domine, in bona voluntate tua Sion: ut aedificentur muri Ierusalem.
Tunc acceptabis sacrificium justitiae, oblationes, et holocausta: tunc imponent super altare tuum vitulos.