Numbers 16:5, 40

and he spake unto Korah and unto all his company, saying, Even to morrow the LORD will shew who are his, and who is holy; and will cause him to come near unto him: even him whom he hath chosen will he cause to come near unto him.

to be a memorial unto the children of Israel, that no stranger, which is not of the seed of Aaron, come near to offer incense before the LORD; that he be not as Korah, and as his company: as the LORD said to him by the hand of Moses.