Leviticus 9:1-24

And so it came to pass on the eighth day that Moses called Aaron and his sons, and the elders of Israel; and he said unto Aaron, Take thee a young calf for a sin offering, and a ram for a burnt offering, without blemish, and offer them before the Lord (Leviticus 9:1-2).

Now Aaron is to begin his ministry. First of all with a calf for a sin offering, a ram for a burnt offering and,

Take ye the kid of the goats for a sin offering; a calf and a lamb, both of the first year, without blemish, for a burnt offering; A bullock and a ram for a peace offering, to sacrifice before the Lord; and a meal offering mingled with oil: for today the Lord will appear unto you (Leviticus 9:3-4).

So he's going to go through the whole route except for the trespass offering. And he's to make all of these offerings; the various types of animals so that Aaron can more or less be schooled in the way that these offerings are to be brought before the Lord. And so they brought that which Moses commanded before the tabernacle.

And Moses said, This is the thing which the Lord commanded you should do: and the glory of the Lord shall appear unto you (Leviticus 9:5).

And so Moses then instructed Aaron. He followed through with him. He went through with him sort of step by step the processes by which the sacrifices were to be made and the methods and all by which they were made. And so they offered first the sin offering, then the consecration offering, then the fellowship offering unto the Lord, and then finally they offered unto God the offering of service, the meal offering.
So in verse twenty-two,

Aaron lifted up his hand toward the people, and blessed them, and came down from offering the sin offering, and the burnt offering, and the peace offering (Leviticus 9:22).

So, having gone in and offered these before the Lord. Now Aaron, the congregation of Israel is out there, and Aaron now comes out and blesses the people, and thus we see the twofold function of the priests. Going before God to represent the people because you and I could not directly come to God. Our sin had separated us from God. So, if I wanted to approach God under the old covenant, I had to come to the priest with an offering, and then he would take and go before God on my behalf. And having gone before God on my behalf he would return and then bless me on God's behalf.
Now later on in Leviticus, we'll get the blessing whereby the people were blessed from God. When Aaron came out, that beautiful blessing that he would put upon the people as he was representing, now, God to the people. So coming out from the sacrifices he now blesses the people as he is God's representative in standing for God before the people, offering God's blessing upon them.

And Moses and Aaron went into the tabernacle of the congregation, and came out, and blessed the people: and the glory of the Lord appeared to all the people (Leviticus 9:23).

Now Moses kept telling them, "You are going to see the glory of the Lord today. Now let's get everything worked out right because today you're going to see the glory of the Lord." And so the glory of the Lord appeared unto all the people. In what form? How? We don't know. But yet they were all made conscious of it and aware of it and in one way it was demonstrated was that

fire came out from before the Lord, and consumed upon the altar the burnt offering and the fat: which when all the people saw, they shouted, and fell upon their faces (Leviticus 9:24).

So, there was the altar; it was there. The wood was there; the pieces of meat of the burnt offering were laid upon it and the fat. And suddenly like a spontaneous combustion fire from the Lord just kindled and the wood began to burn and the sacrifices were consumed. And the people seeing this miracle all began to shout for excitement and fell upon their faces worshipping God.
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