Exodus 29:12
You shall take of the blood of the bull, and put it on the horns of the altar with your finger; and you shall pour out all the blood at the base of the altar.
World English Bible (Public Domain)
In context
Before · Exodus 29:10–11
10“You shall bring the bull before the Tent of Meeting; and Aaron and his sons shall lay their hands on the head of the bull. 11You shall kill the bull before the LORD at the door of the Tent of Meeting.
12You shall take of the blood of the bull, and put it on the horns of the altar with your finger; and you shall pour out all the blood at the base of the altar.