just as the LORD commanded him through Moses. This was to be a reminder to the Israelites that no outsider who is not a descendant of Aaron should approach to offer incense before the LORD, lest he become like Korah and his followers.
KJV
[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.
ASV
to be a memorial unto the children of Israel, to the end that no stranger, that is not of the seed of Aaron, come near to burn incense before Jehovah; that he be not as Korah, and as his company: as Jehovah spake unto him by Moses.