Leviticus 9:21

And the breasts and the right shoulder Aaron waved for a wave offering before the LORD; as Moses commanded.

Leviticus 9:21 belongs to the eighth day of the priests' ministration after the dedication of the tabernacle, when Aaron and his sons performed the offerings God had commanded. The sacrifices offered on that day were accepted by God, who revealed His glory when fire from the Lord came down and consumed the offering upon the altar. At this visible display of divine acceptance, the people responded with praise and adoration.