Charles Ellicott Commentary Numbers 16:28

"And Moses said, Hereby ye shall know that Jehovah hath sent me to do all these works; for [I have] not [done them] of mine own mind." — Numbers 16:28 (ASV)

To do all these works—that is, to bring the people out of the land of Egypt, to exchange the first-born for the Levites, to consecrate Aaron and his sons to the priesthood, and generally to declare the will of the Lord to the people.