For now I will stretch out my hand. It is generally agreed by modern writers that this translation fails to give the true sense of the original God does not here announce what he is going to do, but what he might have done, and would have done, but for certain considerations.
Translate, "For now might I have stretched out my hand, and smitten thee and thy people with pestilence; and then thou hadst been cut off from the earth." Scripture shows that pestilence is always in God's power, and may at any time be let loose to scourge his foes, and sweep them into the pit of destruction.
(See Le Exodus 26:25; Numbers 11:33; Numbers 14:12; Numbers 16:46; 2 Samuel 24:13-15, etc.) He had not done now what he might have done, and what Pharaoh's obstinacy might well have provoked him to do; and why?
On account of the considerations contained in the next verse.