Adultery .... Not only has God forbidden adultery, but the son of God himself said, "Whoso looketh on a woman to lust after her, hath committed adultery with her already in his heart" Matthew 5:28. If the adulterous thought is sin, surely the adulterous act is sin. The Holy Spirit through the inspired apostle has told us plainly that adultery is a sin. Peter described some sinners of his day as having "eyes full of adultery, that cannot cease from sin" II Peter 2:14. Paul warned the Corinthians to "flee fornication" I Corinthians 6:18.