Moses was doing this during the consecration of Aaron and his sons in the tabernacle: 22 Then he presented the second ram, the ram of [j]ordination, and Aaron and his sons laid their hands on the head of the ram. 23 [k]Moses slaughtered it and took some of its blood and put it on the lobe of Aaron’s right ear, and on the thumb of his right hand and on the big toe of his right foot.
Leviticus 8:22 - 23
NKJV - 22 And he brought the second ram, the ram of consecration. Then Aaron and his sons laid their hands on the head of the ram. 23 And Moses killed it. Also he took some of its blood and put it on the tip of Aaron's right ear, on the thumb of his right hand, and on the big toe of his right foot.
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