Leviticus 4:3 - Matthew Poole's English Annotations on the Holy Bible

The priest that is anointed, i.e. the high priest, who only was anointed after the first time. See Exodus 29:7, Exodus 30:30 40:15 Leviticus 10:7 Numbers 3:3. His anointing is mentioned, because he was not complete high priest till he was anointed. Do sin, either in doctrine or practice, which it is here supposed he may do. And this is noted as a blot and character of imperfection in the priesthood of the law, whereby the Israelites were directed to expect another and better High Priest, even one who is holy, harmless, and separate from sinners, Hebrews 7:26. According to the sin of the people; in the same manner as any of the people do, which implies that God expected more circumspection and care from him than from the people. But the words may be rendered, to the sin or guilt of the people, which may be mentioned as a reason of the law, and an aggravation of his sin, that by it he commonly brings sin, and guilt, and punishment upon the people, who are infected or scandalized by his example. A young bullock; the same sacrifice which was offered for all the people, to show how much his sin was aggravated by his quality. For a sin-offering, Heb. sin, which word is oft taken in that sense, as Exodus 29:14.