Albert Barnes Commentary Isaiah 19:22

"And Jehovah will smite Egypt, smiting and healing; and they shall return unto Jehovah, and he will be entreated of them, and will heal them." — Isaiah 19:22 (ASV)

And the Lord shall smite Egypt – That is, in the manner described in the previous part of this prophecy (Isaiah 19:2–10).

And heal it – Or restore it to more than its former splendor and prosperity, as described in the previous verses (Isaiah 19:18–20). He shall send it a saviour; he shall open new sources of prosperity; and he shall cause the true religion to flourish there. These advantages would be more than a compensation for all the calamities that he would bring upon it.

And they shall return ... – These calamities shall be the means of their conversion to Yahweh.