2 But if in Holy Scripture discipline is frequently and everywhere prescribed, and the whole foundation of religion and of faith proceeds from obedience and fear; what is more fitting for us urgently to desire, what more to wish for and to hold fast, than to stand with roots strongly fixed, and with our houses based with solid mass upon the rock unshaken by the storms and whirlwinds of the world, so that we may come by the divine precepts to the rewards of God? Considering as well as knowing that our members, when purged from all the filth of the old contagion by the sanctification of the layer of life, are God's temples, and must not be violated nor polluted, since he who does violence to them is himself injured.
We are the worshippers and priests of those temples; let us obey Him whose we have already begun to be. Paul tells us in his epistles, in which he has formed us to a course of living by divine teaching, “You are not your own, for you are bought with a great price; glorify and bear God in your body.” Let us glorify and bear God in a pure and chaste body, and with a more complete obedience; and since we have been redeemed by the blood of Christ, let us obey and give furtherance to the empire of our Redeemer by all the obedience of service, that nothing impure or profane may be brought into the temple of God, lost He should be offended, and forsake the temple which He inhabits.
The words of the Lord giving health and teaching, as well curing as warning, are: “Behold, you are made whole: sin no more, lest a worse thing come unto you.” He gives the course of life, He gives the law of innocency after He has conferred health, nor suffers the man afterwards to wander with free and unchecked reins, but more severely threatens him who is again enslaved by those same things of which he had been healed, because it is doubtless a smaller fault to have sinned before, while as yet you had not known God's discipline; but there is no further pardon for sinning after you have begun to know God.
And, indeed, let as well men as women, as well boys as girls; let each sex and every age observe this, and take care in this respect, according to the religion and faith which they owe to God, that what is received holy and pure from the condescension of the Lord be preserved with a no less anxious fear.
Source: The Treatises of Cyprian (New Advent)