Many object to the fact of God's sovereign choice in the salvation of sinners on the basis that this would not be fair. It is assumed that God owes man something and whatever He does for one He must do for another. The Holy Spirit obviously knew what man's objection would be and answered it as He inspired the Apostle Paul to write the Roman epistle. What God does is right whether or not man agrees with it or understands it. God does not save men by dealing with them on the basis of fairness.
Fallen man deserves nothing.
God saves entirely by His grace according to His own sovereign will. The Holy Spirit also knew that some would reply that if God is sovereign then He cannot hold man accountable so this objection is also answered. God's sovereignty does not eliminate man's accountability. But Pharaoh acted out of his own sinful pride and was fully responsible for his actions. He was viewed as the Lamb slain from the foundation of the world.