Exodus 7:5 WBT

³  And I will harden Pharaoh's heart, and multiply my signs and my wonders in the land of Egypt.

⁴  But Pharaoh shall not hearken to you, that I may lay my hand upon Egypt, and bring forth my armies, my people the children of Israel, out of the land of Egypt, by great judgments.

⁵  And the Egyptians shall know that I [am] the LORD, when I stretch forth my hand upon Egypt, and bring out the children of Israel from among them.

⁶  And Moses and Aaron did as the LORD commanded them, so did they.

⁷  And Moses [was] eighty years old, and Aaron eighty and three years old, when they spoke to Pharaoh.