All things are lawful for me, but all things are not helpful. All things are lawful for me, but I will not be brought under the power of any. Foods for the stomach and the stomach for foods, but God will destroy both it and them. Now the body is not for sexual immorality but for the Lord, and the Lord for the body. And God both raised up the Lord and will also raise us up by His power. Do you not know that your bodies are members of Christ? Shall I then take the members of Christ and make them members of a harlot? Certainly not! Or do you not know that he who is joined to a harlot is one body with her? For “the two,” He says, “shall become one flesh.” But he who is joined to the Lord is one spirit with Him.
Flee sexual immorality. Every sin that a man does is outside the body, but he who commits sexual immorality sins against his own body. Or do you not know that your body is the temple of the Holy Spirit who is in you, whom you have from God, and you are not your own? For you were bought at a price; therefore glorify God in your body and in your spirit, which are God’s.
Saint Gregory Palamas (d. 1359) comments:
“The apostle urges us once more, brethren, to flee fornication (1 Cor. 6:18). If Samsom had fled from it, he would not have fallen into Delilah’s hands after being deprived of the hair of his head and his strength. He would not have been blinded nor lost his life in such an unfortunate way alongside his enemies (Judg. 14:1). If they who were led by Moses and to whom he had given the law had fled from fornication they would not have made sacrifices to Baal-peor (Num. 25:3), nor eaten sacrifices of the dead (Num. 25:2-3, and cf Ps. 106:28, Hosea 9:10), nor fallen as often as they did. If Solomon had fled from it he would not have deserted God who made him king and gave him wisdom, nor would he have erected temples for idols (1 Kgs. 11:2-4).
You will observe that the passion of fornication pushes a person towards ungodliness. Susanna’s beauty would not have beguiled the senior judges in Babylon, triumphed over them and resulted in their being stoned, if from the beginning they had fled from defilement and had not watched her every day lasciviously beforehand (Sus. 5-62). The wretched Holofernes would not have died with his neck severed if Judith’s sandal had not previously, according to the Scripture, caught his eye and her beauty ensnared his soul (Judith 16:9). Job says, ‘I made a covenant with mine eyes; why then should I think upon a maid’ (Job 31:1), how much less upon a corrupt woman either divorced or married. Practice the single life as dear to God, or the married life as God’s gift. Drink water from your own wells or rather, chastely from your one well. Keep away completely from the adulterated draught, which is the water of the Styx, the stream of the river Acheron. It is full of murderous venom and has poisonous powers, and invariably drags those who drink it down through the trapdoor of hell into its innermost recesses. Flee from the honeyed lips of prostitutes which are skilled in spreading shameful death, namely, separation from God.
David said on the subject, ‘They that wantonly desert thee shall perish’ (Ps. 72:27 Lxx). We, whose bodies have become the temple of God through the Spirit, and in whom the Spirit dwells, must be clean, or at least be in the process of being cleansed, and remain always undefiled, contenting ourselves with permissible pleasures. We must make haste to attain purity and chastity and avoid fornication and every uncleanness, in order to rejoice throughout all ages with the pure bridegroom in the unsullied bridechambers. By the prayers of the ever –virgin, most pure, all-glorious Mother who bore Him in virginity for our salvation, now and for ever and unto the ages or ages. Amen.” (The Homilies, pp 40-41)