of Adam—the very first man—rests a share of its blood (1), for he was the first to introduce murder.
The sin incurred by slaying an innocent victim is therefore immensely grave; the slain person himself never carried a burden comparable to it. Consequently, the murderer returns laden with the sins that had been upon the victim in addition to his own, so that nothing of the wronged man’s guilt remains upon him. Likewise, were the killer to possess any good deeds, the wronged victim would take from them what is due to him—for if the killer were an unbeliever, he would have no good deed at all.
Scholars have differed concerning Cain, the first murderer: was he an unbeliever, or a flagrant sinner who nevertheless remained within the fold of faith? Two opinions exist on the matter.
The Almighty said: “and he became…” Ibn ʿAbbās explained: “of the losers in this world and the Hereafter. His loss in this world was that he angered his parents and was left without a brother; his loss in the Hereafter was that he angered his Lord and entered the Fire.”
Al-Zajjāj commented: “He awoke having forfeited his good deeds.”
Abū Yaʿlā said: “Among those who ruin themselves by destroying it; the loser is the one who loses what he once possessed.” This indicates that his good deeds were wiped out, whether by unbelief or by qisās (retaliatory retribution) (2).