John Gill Commentary Numbers 16:8

"And Moses said unto Korah, Hear now, ye sons of Levi:" — Numbers 16:8 (ASV)

And Moses said unto Korah Continued his discourse to him, as the head of the conspiracy, and the ringleader of it:

hear, I pray you, you sons of Levi ; to whom also he had been before speaking; though Aben Ezra thinks the first speech was made to Korah and his company, and what follows to the Levites.