And the sons of Aaron the priest shall put fire upon the altar, and lay the wood in order upon the fire:

Wesley's Notes

1:7 Put fire - Or, dispose the fire, that is, blow it up, and put it together, so as it might be fit for the present work. For the fire there used and allowed came down from heaven, Lev 9:24, and was to be carefully preserved there, and all other fire was forbidden, Lev 10:1, and c.

Matthew Henry's Concise Commentary

1:3-9 In the due performance of the Levitical ordinances, the mysteries of the spiritual world are represented by corresponding natural objects; and future events are exhibited in these rites. Without this, the whole will seem unmeaning ceremonies. There is in these things a type of the sufferings of the Son of God, who was to be a sacrifice for the sins of the whole world? The burning body of an animal was but a faint representation of that everlasting misery, which we all have deserved; and which our blessed Lord bore in his body and in his soul, when he died under the load of our iniquities. Observe, 1. The beast to be offered must be without blemish. This signified the strength and purity that were in Christ, and the holy life that should be in his people. 2. The owner must offer it of his own free will. What is done in religion, so as to please God, must be done by love. Christ willingly offered himself for us. 3. It must be offered at the door of the tabernacle, where the brazen altar of burnt-offerings stood, which sanctified the gift: he must offer it at the door, as one unworthy to enter, and acknowledging that a sinner can have no communion with God, but by sacrifice. 4. The offerer must put his hand upon the head of his offering, signifying thereby, his desire and hope that it might be accepted from him, to make atonement for him. 5. The sacrifice was to be killed before the Lord, in an orderly manner, and to honour God. It signified also, that in Christians the flesh must be crucified with its corrupt affections and lust. 6. The priests were to sprinkle the blood upon the altar; for the blood being the life, that was it which made atonement. This signified the pacifying and purifying of our consciences, by the sprinkling of the blood of Jesus Christ upon them by faith. 7. The beast was to be divided into several pieces, and then to be burned upon the altar. The burning of the sacrifice signified the sharp sufferings of Christ, and the devout affections with which, as a holy fire, Christians must offer up themselves, their whole spirit, soul, and body, unto God. 8. This is said to be an offering of a sweet savour. As an act of obedience to a Divine command, and a type of Christ, this was well-pleasing to God; and the spiritual sacrifices of Christians are acceptable to God, through Christ, 1Pe 2:5.