Leviticus 9:4
Also a bullock and a ram for peace offerings, to sacrifice before the LORD; and a meat offering mingled with oil: for to day the LORD will appear unto you. Also a bullock and a ram for peace offerings, to sacrifice before the LORD; and a meat offering mingled with oil: for to day the LORD will appear unto you.
On the day the Lord was to appear to the people, a bullock and a ram were appointed for peace offerings, together with a grain offering mingled with oil, to be sacrificed before the Lord. Aaron and his sons offered in that service exactly what God had commanded. God accepted the sacrifice and revealed His glory when fire from the Lord came forth and consumed the offering. The people understood that consuming fire as a manifestation of God's glory and a token of His favor. At the sight they responded with praise and adoration.