It was long the custom of many peoples to dedicate the first fruits to the spirits. And these observances, now more or less symbolic, are all survivals of the early ceremonies involving human sacrifice. The idea of offering the first-born as a sacrifice was widespread among the ancients, especially among the Phoenicians, who were the last to give it up. It used to be said upon sacrificing, "life for life." Now you say at death, "dust to dust."
The spectacle of Abraham constrained to sacrifice his son Isaac, while shocking to civilized susceptibilities, was not a new or strange idea to the men of those days. It was long a prevalent practice for fathers, at times of great emotional stress, to sacrifice their first-born sons. Many peoples have a tradition analogous to this story, for there once existed a world-wide and profound belief that it was necessary to offer a human sacrifice when anything extraordinary or unusual happened.
Moses attempted to end human sacrifices by inaugurating the ransom as a substitute. He established a systematic schedule which enabled his people to escape the worst results of their rash and foolish vows. Lands, properties, and children could be redeemed according to the established fees, which were payable to the priests. Those groups which ceased to sacrifice their first-born soon possessed great advantages over less advanced neighbors who continued these atrocious acts. Many such backward tribes were not only greatly weakened by this loss of sons, but even the succession of leadership was often broken.
An outgrowth of the passing child sacrifice was the custom of smearing blood on the house doorposts for the protection of the first-born. This was often done in connection with one of the sacred feasts of the year, and this ceremony once obtained over most of the world from Mexico to Egypt. (89:6.7)