The burnt-offerings had regard to God as in himself the best of beings, most perfect and excellent; they were purely expressive of adoration, and therefore were wholly burnt. But the peace-offerings had regard to God as a benefactor to his creatures, and the giver of all good things to us; and therefore these were divided between the altar, the priest, and the owner. Peace signifies, 1. Reconciliation, concord, and communion. And so these were called peace-offerings, because in them God and his people did, as it were, feast together, in token of friendship. The priest, who was ordained for men in things pertaining to God, gave part of this peace-offering to God (that part which he required, and it was fit he should be first served), burning it upon God's altar; part he gave to the offerer, to be eaten by him with his family and friends; and part he took to himself, as the days-man that laid his hand upon them both. They could not thus eat together unless they were agreed; so that it was a symbol of friendship and fellowship between God and man, and a confirmation of the covenant of peace. 2. It signifies prosperity and all happiness: Peace be to you was as much as, All good be to you; and so the peace-offerings were offered either, (1.) By way of supplication or request for some good that was wanted and desired. If a man was in the pursuit or expectation of any mercy, he would back his prayer for it with a peace-offering, and probably put up the prayer when he laid his hand upon the head of his offering. Christ is our peace, our peace-offering; for through him alone it is that we can expect to obtain mercy, and an answer of peace to our prayers; and in him an upright prayer shall be acceptable and successful, though we bring not a peace-offering. The less costly our devotions are the more lively and serious they should be. Or, (2.) By way of thanksgiving for some particular mercy received. It is called a peace-offering of thanksgiving, for so it was sometimes; as in other cases a vow, Lev 7:15, Lev 7:16. And some make the original word to signify retribution. When they had received any special mercy, and were enquiring what they should render, this they were directed to render to the God of their mercies as a grateful acknowledgment for the benefit done to them, Psa 116:12. And we must offer to God the sacrifice of praise continually, by Christ our peace; and then this shall please the Lord better than an ox or bullock. Observe,
I. As to the matter of the peace-offering, suppose it was of the herd, it must be without blemish; and, if it was so, it was indifferent whether it was male or female, Lev 3:1. In our spiritual offerings, it is not the sex, but the heart, that God looks at, Gal 3:28.
II. As to the management of it. 1. The offerer was, by a solemn manumission, to transfer his interest in it to God (Lev 3:2), and, with his hand on the head of the sacrifice, to acknowledge the particular mercies for which he designed this a thank-offering, or, if it was a vow, to make his prayer. 2. It must be killed; and, although this might be done in any part of the court, yet it is said to be at the door of the tabernacle, because the mercies received or expected were acknowledged to come from God, and the prayers or praises were directed to him, and both, as it were, through that door. Our Lord Jesus has said, I am the door, for he is indeed the door of the tabernacle. 3. The priest must sprinkle the blood upon the altar, for it was the blood that made atonement for the soul; and, though this was not a sin-offering, yet we must be taught that in all our offerings we must have an eye to Christ as the propitiation for sin, as those who know that the best of their services cannot be accepted unless through him their sins be pardoned. Penitent confessions must always go along with our thankful acknowledgments; and, whatever mercy we pray for, in order to it we must pray for the removal of guilt, as that which keeps good things from us. First take away all iniquity, and then receive us graciously, or give good, Hos 14:2. 4. All the fat of the inwards, that which we call the tallow and suet, with the caul that encloses it and the kidneys in the midst of it, were to be taken away, and burnt upon the altar, as an offering made by fire, Lev 3:3-5. And this was all that was sacrificed to the Lord out of the peace-offering; how the rest was to be disposed of we shall find, Lev 7:11, etc. It is ordered to be burnt upon the burnt-sacrifice, that is, the daily burnt-offering, the lamb which was offered every morning before any other sacrifice was offered; so that the fat of the peace-offerings was an addition to that, and a continuation of it. The great sacrifice of peace, that of the Lamb of God which takes away the sins of the world, prepares the altar for our sacrifices of praise, which are not accepted till we are reconciled. Now the burning of this fat is supposed to signify, (1.) The offering up of our good affections to God in all our prayers and praises. God must have the inwards; for we must pour out our souls, and lift up our hearts, in prayer, and must bless his name with all that is within us. It is required that we be inward with God in every thing wherein we have to do with him. The fat denotes the best and choicest, which must always be devoted to God, who has made for us a feast of fat things. (2.) The mortifying of our corrupt affections and lusts, and the burning up of them by the fire of divine grace, Col 3:5. Then we are truly thankful for former mercies, and prepared to receive further mercy, when we part with our sins, and have our minds cleared from all sensuality by the spirit of judgment and the spirit of burning, Isa 4:4.

Aaron's sons shall burn it - As the fat was deemed the most valuable part of the animal, it was offered in preference to all other parts; and the heathens probably borrowed this custom from the Jews, for they burnt the omentum or caul in honor of their gods.

And Aaron's sons shall burn it on the altar,.... That is, the fat of the several parts before mentioned; this signified the sufferings of Christ, by which our peace is made, and by whose death we are reconciled to God: this rite of burning the fat of the inwards of sacrifices was used by the Pagans, and is still retained by the idolatrous Indians to this day (h):

upon the burnt sacrifice; which, as Gersom says, was the burnt offering of the daily sacrifice of the morning, which was offered first of all sacrifices; so Jarchi says,"we learn that the daily burnt offering preceded every other offering:''this was an eminent type of Christ's sacrifice:

which is upon the wood that is on the fire; that is, which burnt offering was laid upon the wood on the fire, and the fat of the peace offering upon that:

it is an offering made by fire, of a sweet savour unto the Lord; as Christ's sacrifice is, Eph 5:2; see Gill on Lev 1:9.

(h) See the Abridgment of Mr. Brainerd's Journal, published in 1748, p. 30.

the two kidneys . . . of the flock . . . the whole rump--There is, in Eastern countries, a species of sheep the tails of which are not less than four feet and a half in length. These tails are of a substance between fat and marrow. A sheep of this kind weighs sixty or seventy English pounds weight, of which the tail usually weighs fifteen pounds and upwards. This species is by far the most numerous in Arabia, Syria, and Palestine, and, forming probably a large portion in the flocks of the Israelites, it seems to have been the kind that usually bled on the Jewish altars. The extraordinary size and deliciousness of their tails give additional importance to this law. To command by an express law the tail of a certain sheep to be offered in sacrifice to God, might well surprise us; but the wonder ceases, when we are told of those broad-tailed Eastern sheep, and of the extreme delicacy of that part which was so particularly specified in the statute [PAXTON].