Exodus 9:28
Intreat the LORD (for it is enough) that there be no more mighty thunderings and hail; and I will let you go, and ye shall stay no longer. Intreat the LORD (for it is enough) that there be no more mighty thunderings and hail; and I will let you go, and ye shall stay no longer.
The plea was uttered while Pharaoh lay humbled beneath the plague of hail mingled with fire, accompanied by lightning and thunder. The time of each plague had been announced before it came, so its occurrence could not be dismissed as chance. The hail was a demonstration to the Egyptians that the whole earth is under the command of the God of the Hebrews, and that thunder, hail, and storm obey His voice. Moses agreed to intercede for the thunder to cease so that Pharaoh would know the earth belongs to the Lord.
The proud king who had once questioned why he should obey the Lord's voice now admitted his own sin and declared the Lord righteous while he and his people were wicked. He asked Moses and Aaron to entreat the Lord as his intercessors that the mighty thunderings, lightning, and hail might cease, declaring that the plague had gone far enough. With that request he promised to let Israel go and to detain them no longer.
His confession and promise sprang from terror and anguish rather than true repentance or a lasting change of heart, without genuine fear of God. Even as he agreed to intercede, Moses knew that Pharaoh and his servants would not yet fear God. Once the plague ceased, he broke his promise and refused to let the people go, returning to stubbornness. His whole being rising in rebellion against exhibitions of divine power shows that rebellion produces rebellion and that continual opposition hardens the heart.