Seven bullocks... rams... lambs. — For a burnt offering (‘ôlah). See the legal prescriptions respecting the sin offering (Leviticus 4). On the present extraordinary occasion, an extraordinary sacrifice was offered. Balak and Balaam offered seven bullocks and seven rams as a burnt offering (Numbers 23:1-2, seq.).
And seven he goats, for a sin offering. — Comp. Ezra 6:17; Ezra 8:35; and Leviticus 4:23; Leviticus 4:28; also 2 Chronicles 29:23. The reigning house and the sanctuary and the people had all contracted defilement during the late period of idolatry.
The priests the sons of Aaron to offer. — In careful accordance with the rule of the Torah.