14 Vices and carnal sins must be trampled down, beloved brethren, and the corrupting plague of the earthly body must be trodden under foot with spiritual vigour, lest, while we are turned back again to the conversation of the old man, we be entangled in deadly snares, even as the apostle, with foresight and wholesomeness, forewarned us of this very thing, and said: “Therefore, brethren, let us not live after the flesh; for if you live after the flesh, you shall begin to die; but if you, through the Spirit, mortify the deeds of the flesh, you shall live.
For as many as are led by the Spirit of God they are the sons of God.” If we are the sons of God, if we are already beginning to be His temples, if, having received the Holy Spirit, we are living holily and spiritually, if we have raised our eyes from earth to heaven, if we have lifted our hearts, filled with God and Christ, to things above and divine, let us do nothing but what is worthy of God and Christ, even as the apostle arouses and exhorts us, saying: “If you be risen with Christ, seek those things which are above, where Christ is sitting at the right hand of God; occupy your minds with things that are above, not with things which are upon the earth.
For you are dead, and your life is hid with Christ in God. But when Christ, who is your life, shall appear, then shall you also appear with Him in glory.” Let us, then, who in baptism have both died and been buried in respect of the carnal sins of the old man, who have risen again with Christ in the heavenly regeneration, both think upon and do the things which are Christ's, even as the same apostle again teaches and counsels, saying: “The first man is of the dust of the earth; the second man is from heaven.
Such as he is from the earth, such also are they who are from the earth and such as He the heavenly is, such also are they who are heavenly. As we have borne the image of him who is of the earth, let us also bear the image of Him who is from heaven.” But we cannot bear the heavenly image, unless in that condition wherein we have already begun to be, we show forth the likeness of Christ.
Source: The Treatises of Cyprian (New Advent)