Romans 9:17-18

¹⁷ For the Scripture says to the Pharaoh, “For this very purpose I have raised you up, that I may show My power in you, and that My name may be declared in all the earth.”

¹⁸ Therefore He has mercy on whom He wills, and whom He wills He hardens.

Scripture saith — And in very deed for this cause have I raised thee up, for to shew in thee My power; and that My name may be declared throughout all the earth (Exodus 9:16).

Raise thee up = stand — Made him king and kept him king

He has mercy — And He said, I will make all my goodness pass before thee, and I will proclaim the name of the LORD before thee; and will be gracious to whom I will be gracious, and will shew mercy on whom I will shew mercy (Exodus 33:19).

Hardeneth — Pharaoh hardened his own heart first (Exodus 5:2; 7:3). Then God gave him over (Exodus 5:21; 7:23; 9:12; 10:1; 10:20-27; 11:10; 14:4,8).

As a matter of fact, the narrative in Exodus states that to begin with, Pharaoh persistently hardened his own heart. The whole record is deeply significant in this respect. Firstly, Exodus 3:19 establishes the prescience of God. Then 4:21 simply foretells what God will do as to Pharaoh’s conduct. The effects of the first plagues were that Pharaoh was responsible for hardening his own heart. At 9:12, we find the statement of the Lord’s intervention in this matter; “The Lord hardened the heart of Pharaoh.” Yet again in 9:35 the hardening is ascribed to the monarch. After that in each case it is ascribed to God (10:1, 20; 11:10). Clearly, therefore, the hardening was retributive and not arbitrary. Yet, while God did not make Pharaoh wicked, and his punishment was nothing more than he deserved, the argument in Romans stresses the absolute sovereignty and righteousness of God. The recipient of pardoning mercy can never boast in his priority of merit. He who is punished can never charge God with unrighteousness.

This idea, therefore, is not merely Pharaoh’s exaltation to kingship but his being maintained in that position instead of being immediately cut off for his self-will. Not the creation of the man is in view but the object for which God permitted him so long to be kept in authority. — Vine, page 144.