From Dom Guéranger's The Liturgical Year.
O God of infinite justice! we have sinned; we have abused the life Thou hast given us: and when we read, in Thy Scriptures, how Thine anger chastised the sinners of former days, we are forced to acknowledge, that we have deserved to be treated in like manner. We have the happiness to be Christians and children of Thy Church; the light of faith, and the power of Thy grace, have brought us once more into Thy friendship; but how can we forget that we were once Thy enemies? And are we so deeply rooted in virtue, that we can promise ourselves perseverance in it to the end? Pierce, O Lord! pierce my flesh with Thy fear.[1] Man’s heart is hard, and unless it fear Thy sovereign Majesty, it may again offend Thee.
We are penetrated with fear, when we remember that Thou didst bury the world and destroy mankind by the waters of the deluge; for we learn by this, how Thy patience and long-suffering may be changed into inexorable anger. Thou art just, O Lord! and who shall presume to take scandal, or to murmur, when Thy wrath is enkindled against sinners?
We have defied Thy justice, we have braved Thine anger; for, though Thou hast told us that Thou wilt never more destroy sinners by a deluge of water, yet we know that Thou hast created, in Thy hatred for sin, a fire, which shall eternally prey on them that depart this life without being first reconciled with Thy offended Majesty.
O wonderful dignity of our human nature! We cannot be indifferent towards that infinite Being that created us: we must be His friends or His enemies! It could not have been otherwise. Ile gave us understanding and free-will: we know what is good and what is evil, and we must choose the one or the other: we cannot remain neutral. If we choose good, God turns towards us and loves us; if evil, we separate from Him, who is our sovereign Good. But, whereas He bears most tender mercy towards this frail creature whom He created out of pure love, and because He wills that all men should be saved, He waits with patience for the sinner to return to Him, and, in countless ways, draws his heart to repentance.
But woe to him that obeys not the divine call, when that call is the last! Then justice takes the place of mercy, and revelation tells us how fearful a thing it is to fall into the hands of the living God.[2] Let us, then, flee from the wrath to come,[3] by making our peace with the God we have offended. If we be already restored to grace, let us walk in His fear, until love shall have grown strong enough in our hearts to make us run the way of the commandments.[4]
The following prayer is from the Mozarabic breviary of the Gothic Church of Spain.
Oratio
(In capite jejunii.)
Averte faciem tuam a peccatis nostris, Domine, et omnes iniquitates nostras dele; remove ab oculis tuis malarum nostrarum facinus voluptatum, nostræque confessioni clementer tuum appone auditum. Miserere, quæsumus, rogantibus nobis, qui propitius respicis in adversis, et qui desperatis cor pœnitens tribuis ad confessionem gloriæ tuæ. Sed quia publicanus a longe stans et percutiens pectus suum, sola confessione purgatus est, similiter et nos peccatores exaudi; ut sicut illi meritospetitionis suæ fructus donasti, ita et nobis supplicantibus indignis servistuis veniam digneris impendere peccatis. Amen.
Turn away thy face from our sins, O Lord, and blot out all our iniquities. Take from thine eyes the guilt of our sinful pleasures, and mercifully incline thine ear to our confession. Have mercy, we beseech thee, upon us thy suppliants, O thou that lookest with pity on them that are in affliction, and givest to the disconsolate a penitent heart, that so they may praise thy name. The publican who stood afar off and struck his breast, found forgiveness by this alone, that he confessed his sin; do thou, in like manner, mercifully hear us sinners and as thou didst give to him the fruit his prayer deserved, so also vouchsafe to grant unto us, thy suppliant unworthy servants, the pardon of our sins. Amen.
[1] Ps. cxviii. 120.
[2] Heb. x. 31.
[3] St. Matt. iii. 7.
[4] Ps. cxviii. 32.