Leviticus 9:22

Something of this sort has also been written about Aaron in the book of Leviticus, namely, that "he raised up his hands over the people and blessed them." I gather from this that the saying expresses a mystery, namely, that the one who blesses someone must be adorned with works that distinguish him from the many and raise him above them. For when he is going to bless the people, the hands of Aaron are raised on high. So if someone has his hands down toward earthly things, he does not intend to bless anyone.

And he continues: And Aaron, lifting up his hands toward the people, blessed them and went down, having offered the sin offering, and the burnt offerings and the sacrifice of salvation. What does this mean? Where did he do this but on the altar, standing next to the altar and serving the altar? Therefore, he came down from where he was. It seems clear that the solution to that question that we had raised in the Exodus about how he could have served the altar, which was three cubits high, can benefit from this testimony. There we were forbidden to admit that they were tiered, because God had forbidden it, so that the prudent parts of the officiant would not be exposed on the altar, which would happen if the step was a part of the altar, that is, if it were united in compact form. Finally, this was forbidden there where it was an altar made of several pieces. For the altar would be a thing with the tier, and the tier would be a part of the altar, and that is why it was forbidden. But here, where the height of the altar had been so great that if the priest had not been standing on something, could not properly officiate, you have to understand that whatever it was that was put and removed during the time of the offices, was not a part of the altar and, therefore, did not go against the precept that prohibited the altar had tiers. The Scripture omitted to speak of this, whatever it was, and that is why the problem has arisen. But now, when he says that the priest, when he offered the sacrifices, came down, after placing the immolated things on the altar, it is evident, evidently, that the priest had to be somewhere so that he could get down from there. And since he had been there, he could serve and officiate at an altar three cubits high.