Did not the burning imply, the just wrath of God for sin? Hebrews 12:29.
Related Commentaries of Leviticus 1:7
Leviticus 1:7-8
7 And the sons of Aaron the priest shall put fire upon the altar, and lay the wood in order upon the fire:
8 And the priests, Aaron's sons, shall lay the parts, the head, and the fat, in order upon the wood that is on the fire which is upon the altar: