leviticus 17:3 What man soever there be of the house of Israel, that killeth an ox, or lamb, or goat, in the camp, or that killeth it out of the camp, - Free Bible Online

      3, 4. What man . . . killeth an ox--The Israelites, like other people living in the desert, would not make much use of animal food; and when they did kill a lamb or a kid for food, it would almost always be, as in Abraham's entertainment of the angels [Ge 18:7], an occasion of a feast, to be eaten in company. This was what was done with the peace offerings, and accordingly it is here enacted, that the same course shall be followed in slaughtering the animals as in the case of those offerings, namely, that they should be killed publicly, and after being devoted to God, partaken of by the offerers. This law, it is obvious, could only be observable in the wilderness while the people were encamped within an accessible distance from the tabernacle. The reason for it is to be found in the strong addictedness of the Israelites to idolatry at the time of their departure from Egypt; and as it would have been easy for any by killing an animal to sacrifice privately to a favorite object of worship, a strict prohibition was made against their slaughtering at home. (See on De 12:15).

JFB.