43 Concerning continence also itself has it not been most openly said, “And when I knew that no one can be continent unless God give it, this also itself was a part of wisdom, to know whose gift it was?” But perhaps continence is the gift of God, but wisdom man bestows upon himself, whereby to understand, that that gift is, not his own, but of God. Yea, “The Lord makes wise the blind:” and, “The testimony of the Lord is faithful, it gives wisdom unto little ones:” and, “If any one want wisdom, let him ask of God, Who gives unto all liberally, and upbraids not, and it shall be given to him.” But it becomes virgins to be wise, that their lamps be not extinguished. How “wise,” save “not having high thoughts, but consenting unto the lowly.” For Wisdom Itself has said unto man, “Lo, piety is wisdom!” If therefore you have nothing, which you have not received, “Be not high-minded, but fear.” And love not little, as though Him by Whom little has been forgiven to you; but, rather, love Him much, by Whom much has been given to you.
For if he loves, unto whom it has been given not to repay: how much more ought he to love, unto whom it has been given to possess. For both, whosoever continues chaste from the beginning, is ruled by Him; and whosoever is made chaste instead of unchaste, is corrected by Him; and whosoever is unchaste even unto the end, is abandoned by Him. But this He can do by secret counsel, by unrighteous He cannot: and perhaps it is for this end that it lies hid, that there may be more fear, and less pride.
Source: On Holy Virginity (New Advent)