Exodus 11:10

And Moses and Aaron did all these wonders before Pharaoh, Which are related in the preceding chapters:

and the Lord hardened Pharaoh's heart: one time after another, and yet more and more:

so that…

Warning is here given to Pharaoh of the last and conquering plague which was now to be inflicted. This was the death of all the first-born in Egypt at once, which had been first threatened (Exo 4:23,…