Charles Ellicott Commentary Leviticus 1:3

"If his oblation be a burnt-offering of the herd, he shall offer it a male without blemish: he shall offer it at the door of the tent of meeting, that he may be accepted before Jehovah." — Leviticus 1:3 (ASV)

If his offering is a burnt sacrifice. —Having stated what is meant by animals, the directions now address the different kinds of the offerings themselves. First in order comes the burnt offering, which is divided into burnt offering from the cattle (Leviticus 1:3–9), and burnt offering from the flock (Leviticus 1:10–13). The ox takes precedence because it is the more costly and more important sacrifice. It had to be without disease or blemish of any kind.

To offer a defective sacrifice was an insult and a deception. Hence the exclamation of the prophet, cursed be the deceiver which hath in his flock a male and voweth and sacrificeth unto the Lord a corrupt thing (i.e., an animal with a blemish), Malachi 1:14. The offerer is to bring the animal to the entrance of the tent of meeting, as it should be rendered, that is, to the front of the Tabernacle where the brazen altar stood (Exodus 40:6).

Of his own voluntary will. —The whole passage is better rendered, at the entrance of the tent of meeting he shall offer it, that he may be accepted before the Lord. (Leviticus 19:5; Leviticus 22:19–20; Leviticus 22:29; Leviticus 23:11.) This meaning is unmistakably presented in Leviticus 22:19-21, where it is explicitly declared, ye shall offer for your acceptance a male without blemish of the beeves, of the sheep or of the goats, but whatsoever hath a blemish that ye shall not offer, for it shall not be acceptable for you. It should be noted that the phrase “for your acceptance,” or “acceptable for you,” is only used in connection with burnt offerings and peace offerings, but never with sin offerings.