23 The first decree commanded to increase and to multiply; the second enjoined continency. While the world is still rough and void, we are propagated by the fruitful begetting of numbers, and we increase to the enlargement of the human race. Now, when the world is filled and the earth supplied, they who can receive continency, living after the manner of eunuchs, are made eunuchs unto the kingdom. Nor does the Lord command this, but He exhorts it; nor does He impose the yoke of necessity, since the free choice of the will is left.
But when He says that in His Father's house are many mansions, He points out the dwellings of the better habitation. Those better habitations you are seeking; cutting away the desires of the flesh, you obtain the reward of a greater grace in the heavenly home. All indeed who attain to the divine gift and inheritance by the sanctification of baptism, therein put off the old man by the grace of the saving layer, and, renewed by the Holy Spirit from the filth of the old contagion, are purged by a second nativity.
But the greater holiness and truth of that repeated birth belongs to you, who have no longer any desires of the flesh and of the body. Only the things which belong to virtue and the Spirit have remained in you to glory. It is the apostle's word whom the Lord called His chosen vessel, whom God sent to proclaim the heavenly command: “The first man,” says he, “is from the earth, of earth; the second man is from heaven. Such as is the earthy, such are they also who are earthy; and such as is the heavenly, such also are the heavenly.
As we have borne the image of him who is earthy, let us also bear the image of Him who is heavenly.” Virginity bears this image, integrity bears it, holiness bears it, and truth. Disciplines which are mindful of God bear it, retaining righteousness with religion, steadfast in faith, humble in fear, brave to all suffering, meek to sustain wrong, easy to show mercy, of one mind and one heart in fraternal peace.
Source: The Treatises of Cyprian (New Advent)