Charles Ellicott Commentary Exodus 6:1

"And Jehovah said unto Moses, Now shalt thou see what I will do to Pharaoh: for by a strong hand shall he let them go, and by a strong hand shall he drive them out of his land." — Exodus 6:1 (ASV)

Now you will see. —Moses’ complaint was that God delayed, and “was slack concerning His promise.” Until now He had not “delivered His people at all.” The answer, “Now you will see,” is an assurance that there will be no more delay; the work is just about to begin, and Moses will behold it. He will then cease to doubt.

With a strong hand he will let them go. —Rather, through a strong hand: i.e., through the compulsion which my strong hand will exert on him.

Drive them. —Compare Exodus 12:31-33.