(9) And the sons of Aaron brought the blood.--His sons, for whom the sacrifice was offered as well as for himself, and who assisted at the ritual, after catching the blood in a bowl (see Leviticus 1:5), brought it to Aaron, who stood at the altar waiting to receive it. Unlike the ordinary law of the sin offering for the high priest and for the people, the blood of which was taken into the tabernacle (see Leviticus 4:7; Leviticus 4:16-18), Aaron on this occasion simply put some of it upon the four horns of the brazen altar as Moses had done in the sin offering of consecration (see Leviticus 8:15), for, though high priest, he had not as yet access to the holy place of the sanctuary till he had qualified himself by this sacrifice in the court-yard.

Matthew Henry's Concise Commentary

9:1-21 These many sacrifices, which were all done away by the death of Christ, teach us that our best services need washing in his blood, and that the guilt of our best sacrifices needs to be done away by one more pure and more noble than they. Let us be thankful that we have such a High Priest. The priests had not a day's respite from service allowed. God's spiritual priests have constant work, which the duty of every day requires; they that would give up their account with joy, must redeem time. The glory of God appeared in the sight of the people, and owned what they had done. We are not now to expect such appearances, but God draws nigh to those who draw nigh to him, and the offerings of faith are acceptable to him; though the sacrifices being spiritual, the tokens of the acceptance are spiritual likewise. When Aaron had done all that was to be done about the sacrifices, he lifted up his hands towards the people, and blessed them. Aaron could but crave a blessing, God alone can command it.

Gill's Exposition of the Entire Bible

And the sons of Aaron brought the blood unto him,.... The blood of the calf of the sin offering, which they had received in a basin when it was slain:

and he dipped his finger in the blood, and put it upon the horns of the altar; the four horns of it, as Moses had done at his consecration, which was an example to him, Leviticus 8:15. This was typical of the blood of Christ, to which persons may have recourse from the four quarters of the world for atonement and pardon:

and poured out the blood at the bottom of the altar; what remained after he had put what was proper on the horns of it.

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