Charles Ellicott Commentary Psalms 106:28

"They joined themselves also unto Baal-peor, And ate the sacrifices of the dead." — Psalms 106:28 (ASV)

Ate the sacrifices of the dead — that is, the sacrifices of a dead divinity. Numbers 25:2, and they called the people unto the sacrifices of their gods, shows that here we must not see any allusion to necromantic rites, such as are referred to in Deuteronomy 18:11; Isaiah 8:19. The parallelism shows that the “god” in question is Baal-peor.

Carcases of idols. — This phrase is actually used in Leviticus 26:30; here no doubt the plural is used poetically for the singular.