Leviticus 17:3

What man soever [there be] of the house of Israel
Whether high or low, rich or poor:

that killeth an ox, or lamb, or goat in the camp;
which are particularly mentioned, as Gersom observes, because of these the offerings were; for the law respects the killing of them not for common food, but for sacrifice, as appears from the following verses; for this law was to be a statute for ever, whereas in that sense it was not, and could not be observed, especially when they were come into the land of Canaan; nor would it have been decent or convenient to have brought such vast numbers of cattle every day to be killed at the door of the tabernacle, and must have made the service of the priests extremely laborious to kill them, or even to see that they were killed aright:

or that killeth [it] out of the camp;
which furnishes out another reason against the same notion, since it was not usual to kill for common food without the camp, but in their own tents within it; whereas to sacrifice without the camp was commonly done.