4:19–24 Lamech. Lamech represents both a progressive hardening in sin—polygamy (cf. 2:24; Matt. 19:5, 6) and a grossly unjust vendetta—and the extension of the cultural mandate from animal husbandry (v. 20) to the arts (v. 21) and sciences (v. 22). Lamech expresses, indeed celebrates, his deepening depravity by his song (vv. 23, 24).