Chastity:
You don’t have sex until you get lawfully married, and then you have sex with no one but the one person you are lawfully married to. You remain faithful to that person for the rest of your life, unless that person is guilty of unchastity.
By “lawfully,†I mean, “By the law of the Lord.â€
[20] And he said, "What comes out of a man is what defiles a man.
[21] For from within, out of the heart of man, come evil thoughts, fornication, theft, murder, adultery,
[22] coveting, wickedness, deceit, licentiousness, envy, slander, pride, foolishness.
[23] All these evil things come from within, and they defile a man." Mark 7:20-23 RSV
But I say to you that every one who looks at a woman lustfully has already committed adultery with her in his heart. Matt 5:28 RSV
[32] But I say to you that every one who divorces his wife, except on the ground of unchastity, makes her an adulteress; and whoever marries a divorced woman commits adultery. Matt 5:32 RSV