Matthew 5:28

But I say. See v. 22. Jesus bases His teaching on God’s original marriage plan (Gen. 2:21-24; Matt. 19:8), not Mosaic law (Deut. 24:1-4). Marriage was for companionship (Gen. 2:18) and child-rearing (Gen. 1:28; 18:19; Prov. 22:6; Eph. 6:1-4). The home was ideal for learning God and developing character.

Looketh on a woman. Feminine beauty is a gift from the Creator, who loves true beauty. Pure appreciation is right and proper. Attraction between sexes is implanted by God and inherently good within limits but destructive when perverted.

Lust. Greek epithumeo, “to set one’s heart upon,” “to long for,” “to covet,” “to desire.” “Lust” is an old Anglo-Saxon word meaning “pleasure,” “longing.” Epithumeo is used in good and evil senses (Luke 22:15; Matt. 13:17; Luke 17:22; Heb. 6:11; 1 Peter 1:12).

The related noun epithumia, “desire,” is used similarly (Phil. 1:23; 1 Thess. 2:17). Hebrew equivalent chamad means “to desire,” “to take pleasure in,” rendered “covet” in the tenth commandment (Ex. 20:17) and “desire” in Deut. 5:21 and Isa. 53:2. Jesus likely referred to the tenth commandment when warning against lusting after a woman.

Heart. Greek kardia, referring to intellect, affections, and will. “As a man thinketh in his heart, so is he” (Prov. 23:7). Character is determined by inward attitude, not outward act. Outward acts reflect inward decisions. One guilty before God is he who would sin if undetected. Sin is primarily an act of mind and will (Prov. 7:19).