Jamieson, Fausset and Brown on Leviticus 1:2

2. Speak unto the children of Israel, and say unto them--If the subject of communication were of a temporal nature, the Levites were excluded; but if it were a spiritual matter, all the tribes were comprehended under this name (De 27:12).

If any man of you bring an offering unto the Lord--The directions given here relate solely to voluntary or freewill offerings--those rendered over and above such, as being of standing and universal obligation, could not be dispensed with or commuted for any other kind of offering (Ex 29:38; Le 23:37; Nu 28:3, 11-27, &c.).

bring your offering of the cattle, &c.--that is, those animals that were not only tame, innocent and gentle, but useful and adapted for food. This rule excluded horses, dogs, swine, camels, and asses, which were used in sacrifice by some heathen nations, beasts and birds of prey, as also hares and deers.