They shall therefore keep mine ordinance,.... The observance of my word, as the Targums of Onkelos and Jonathan, of his word of command; either respecting the not eating of such creatures that died of themselves, or were torn by beasts; or else the not eating holy things in uncleanness, so Jarchi and Gersom; but Aben Ezra thinks the sanctuary is referred to, which was to be kept by the priests, and which seems to agree with what follows:
lest they bear sin for it: the sanctuary, by neglecting it, and so be charged with the guilt of sin, and be obliged to bear the punishment of it:
and die therefore if they profane it; by going into it in their uncleanness, and eating of the most holy things there when in such circumstances, and die by the hand of God, as Jarchi and Ben Gersom interpret it, as Nadab and Abihu did, and even in like manner, by fire, Leviticus 10:1; and so the Targum of Jonathan,"lest they die by flaming fire:"
I the Lord do sanctify them; the priests, who were separated from others, and devoted to his service, and therefore ought to be holy; or the holy things separated for the use of the priests, but not to be eaten in their uncleanness; the Arabic version renders it, "do sanctify that", the sanctuary, and therefore it should not be profaned, but be kept pure and holy.

Lest they bear sin - Incur guilt and punishment. For it - For the neglect or violation of it.