en_tn_condensed/gen/04/15.md

vengeance will be taken on him sevenfold

This can be stated in active form. AT: "I will take vengeance on him seven times" or "I will punish that person seven times as severely as I am punishing you" (See: rc://en/ta/man/translate/figs-activepassive)

would not attack him

"would not kill Cain"