Tertullian - On Exhortation to Chastity

No one deserves (favor) by availing himself of the indulgence, but by rendering a prompt obedience to the will, (of his master). The will of God is our sanctification, for He wishes His “image”—us—to become likewise His “likeness;” that we may be “holy” just as Himself is “holy.” That good—sanctification, I mean—I distribute into several species, that in some one of those species we may be found. The first species is, virginity from one’s birth: the second, virginity from one’s second birth, that is, from the font; which (second virginity) either in the marriage state keeps (its subject) pure by mutual compact, or else perseveres in widowhood from choice: a third grade remains, monogamy, when, after the interception of a marriage once contracted, there is thereafter a renunciation of sexual connection. The first virginity is (the virginity) of happiness, (and consists in) total ignorance of that from which you will afterwards wish to be freed: the second, of virtue, (and consists in) contemning that the power of which you know full well: the remaining species, (that) of marrying no more after the disjunction of matrimony by death, besides being the glory of virtue, is (the glory) of moderation likewise; for moderation is the not regretting a thing which has been taken away, and taken away by the Lord God, without whose will neither does a leaf glide down from a tree, nor a sparrow of one farthing’s worth fall to the earth.