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Ezekiel 25:15-17 Thus saith the Lord GOD; Because the Philistines have dealt by revenge, and have taken vengeance with a despiteful heart, to destroy it for the old hatred; Therefore thus saith the Lord GOD; Behold, I will stretch out mine hand upon the Philistines, and I will cut off the Cherethims, and destroy the remnant of the sea coast. And I will execute great vengeance upon them with furious rebukes; and they shall know that I am the LORD, when I shall lay my vengeance upon them.

The idea of punishment in the Death Wish films is seemingly taken from the Old Testament, where God dishes out punishment to anyone who breaks the rules as they happen, without having them wait to get their comeuppance in the afterlife. Leviticus 24:18 states `if after all this you will not listen to me, I will punish you for your sins seven times over`. In the Death Wish series, not all of Kersey's violence is purely based on his own feelings of revenge, but he "takes care of" other criminals who will harm others. The entirety of Death Wish 4 is based on Kersey hunting and systematically destroying drug cartels in Los Angeles, after his step-daughter over-doses on cocaine early in the film. Kersey feels that he must wipe out these dangerous groups for the betterment of society, like a much less homophobic manifestation of God's wrath in Sodom and Gomorrah. The vice portrayed, and the preying on the naive and innocent infuriates the once again mild-mannered architect, who must go back to his old ways, and arm himself with the machine gun and grenades hidden behind the fridge in his condo. While some of his motivation is based on his step-daughters death, it extends beyond just killing the one dealer who provided the drugs to her. He works his way up, before finally killing three entire crime syndicates single handedly.

Genesis 9:6 states "Whoever shed man’s blood, by man his blood shall be shed", and this sums up Paul Kersey's ideology perfectly.