To be a memorial unto the children of Israel, that no stranger, who is not of the descendants of Aaron, come near to offer incense before the LORD; that he become not as Korah, and as his company: as the LORD said to him by the hand of Moses.
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George Leo Haydock
Stranger, though he be even of royal dignity. Thus Osias was afflicted with a perpetual leprosy, which rendered him incapable of exercising even the office of king, because he had attempted to offer incense, 2 Kings xv. 5., and 2 Paralipomenon xxvi. 17. (Haydock)