Chapter 10
Aaron's sons, Nadab and Abihu, offer incense that the Lord had not commanded them, and fire came out and consumed them. MSB says the details are really unknown, but it is possible that they were drunk at the time they did this. Also, fire for the incense was to come from the brazen altar, but that's not where they got it. They got it from someplace else, so it was "unauthorized" fire. Considering what they had just seen, fire coming down and consuming the offering, their action should be seen as careless, irreverent and pretty thoughtless of the possible consequences.
2025 Addendum - See Ex 30:9. They were not to offer anything outside the instructed parameters. Plus this was in the Holy Place. Were they even supposed to be in there? This passage is very good context.
9 You shall not offer unauthorized incense on it, or a burnt offering, or a grain offering, and you shall not pour a drink offering on it. [Exo 30:9 ESV]
9 "Drink no wine or strong drink, you or your sons with you, when you go into the tent of meeting, lest you die. It shall be a statute forever throughout your generations. [Lev 10:9 ESV]
This seems to be a new rule, perhaps as a consequence of what Nadab and Abihu had done. No alcohol of any kind for Aaron, or indeed any that are performing a priestly function.
Eleazar and Ithamar are "promoted" to take the place of Nadab and Abihu. But when they first offer the sin offering, they do it wrong. They burn up the whole animal, when they were supposed to keep certain portions as their due. This verse:
17 "Why have you not eaten the sin offering in the place of the sanctuary, since it is a thing most holy and has been given to you that you may bear the iniquity of the congregation, to make atonement for them before the LORD? [Lev 10:17 ESV]
This one had to be eaten in a holy place. In vs 15, the breast and the thigh of that sacrifice was to be eaten in a "clean" place, as opposed to a holy place, and with the whole family of the priest. This was the part of the wave offering - which is a subset of the peace offering.
Notes from MSB: The issue Moses had was that instead of being eaten, they had taken part of the sin offering outside the camp and burned it there. This was supposed to be eaten as a sacred feast. Moses braces the sons of Aaron about this, rather than Aaron himself, because Aaron has already lost two sons, and might well have feared that he was about to lose the other two. Moses confronts Eleazar and Ithamar, but Aaron overhears. Aaron says all was done properly up to the point when they were to feast on the thigh and breast. Aaron says they did not eat because of his dejected attitude at the loss of his sons. He was in no state to have a "feast". Aaron implies that the sin of feasting with the wrong attitude might have been worse than not finishing the sin offering properly. Moses acquiesces to this explanation.
2021 - The wording of 17 is interesting. "...given to you that you may bear the iniquity of the congregation..." So symbolically, the sins of the one making the sin offering - whether individually or corporate Israel - are transferred onto the sin offering itself. By eating some of this sin offering, the priests are "incorporating" that sin into themselves - they are "bearing" the sin of another, making it a part of them, transferring it to themselves from the one making the offering. See how this ties to the substitutionary death of Jesus on the cross? All the sin was transferred onto him, as priest, and it was therefore his to atone for. He did this atoning by the shedding of blood, just as the priests made daily sin offerings for themselves and for the people. In the whole scheme of these things, sin is moved from the common to the holy, and God forebears with the Holy because of their position as priests. And Jesus stands today at the right hand of God, constantly making intercession for us. It all fits together. Nobody could make this up and make it fit like this. This is not the cumulative imagination of men fitting all this together, only a Holy God could maintain such a process over so long a chronology. It is plain to see. This is why pleading ignorance doesn't work. Anyone who looks can see it.
2023 - So Jesus took the sin of the world onto himself - because he was in fact THE sacrifice - and he dealt with it, bearing "the iniquity of the congregation", in this case the whole world, AS OUR PRIEST. He therefore took it directly onto himself, he did not have to "eat the sacrifice" in order to take it on himself. In the Lord's supper, WE are symbolically eating a part of the atoning sacrifice for us, and as our own priests, connecting ourselves with the one sacrificed for us. Taking his sacrifice into ourselves. So...I have never so appreciated what the Lord's supper is about, nor the reason we are all priests, as correctly as I do right now. Even so, I still don't understand WHY WE DRINK THE BLOOD???? Jesus died outside the camp, which is where the parts not eaten were taken. So I need to look into that. I think it is connected to Moses meeting God outside the camp when he would intervene for the people prior to construction of the tent of meeting. It may also have something to do with the scapegoat and the ritual surrounding that. It may be that each of these ceremonies/procedures/sacrifices sort of "touches" the passion of Christ in part - symbolically acceptable to God - but none encompasses the whole future work of Christ. The rituals all foreshadowed the crucifixion in some perceptible way, but not is as encompassing as Jesus on the cross.
Chapters 8 and 9 are a good "walk through" of the sacrifices that were regularly made. We saw the regulations concerning these sacrifices given, and then we see how they are carried out in practice. We see the consequences of irreverent worship, and chastisement for procedural, though apparently unwitting, mistakes by the priests.