He: i.e. Jehovah.
said. See note on Numbers 3:40.
If there be. should there be; i.e. when ye have your prophet.
make Myself known. This also essential to. prophet. Compare Numbers 11:29.
Related Commentaries of Numbers 12:6
Numbers 12:6
6 And he said, Hear now my words: If there be a prophet among you, I the LORD will make myself known unto him in a vision, and will speak unto him in a dream.