John Wesley on Leviticus 9:9

The altar - Of burnt - offering, of which alone he speaks both in the foregoing and following words; and the blood was poured out at the bottom of this altar only, not of the altar of incense, as appears from Lev 4:7, where indeed there is mention of putting some of the blood upon the horns of the altar of incense, in this case of the priest's sacrificing for his own sins. But there seems to be a double difference, That sacrifice was offered for some particular sin, this for his sins indefinitely. There he is supposed to be compleat in his office, and here he is but entering into his office, and therefore must prepare and sanctify himself by this offering upon the brazen altar in the court, before he can be admitted into the holy place where the altar of incense was. And the like is to be said for the difference between the sin - offering for the people here, and Lev 4:17,18.