Easton's Bible Dictionary (1897)/Burnt offering
Burnt offering : Hebrew olah; i.e., "ascending," the whole being consumed by fire, and regarded as ascending to God while being consumed. Part of every offering was burnt in the sacred fire, but this was wholly burnt, a "whole burnt offering." It was the most frequent form of sacrifice, and apparently the only one mentioned in the book of Genesis. Such were the sacrifices offered by Abel (Gen. 4:3, 4, here called minhah; i.e., "a gift"), Noah (Gen. 8:20), Abraham (Gen. 22:2, 7, 8, 13), and by the Hebrews in Egypt (Ex. 10:25).
The law of Moses afterwards prescribed the occasions and the manner in which burnt sacrifices were to be offered. There were "the continual burnt offering" (Ex. 29:38-42; Lev. 6:9-13), "the burnt offering of every sabbath," which was double the daily one (Num. 28:9, 10), "the burnt offering of every month" (28:11-15), the offerings at the Passover (19-23), at Pentecost (Lev. 23:16), the feast of Trumpets (23:23-25), and on the day of Atonement (Lev. 16).
Free-will burnt offerings were also permitted (Lev. 1:13), and were offered at the accession of Solomon to the throne (1 Chr. 29:21), and at the reformation brought about by Hezekiah (2 Chr. 29: 31-35).