ISB ~ Romans 9 v18

he has mercy … he hardens:The pattern of God’s dealings with Israel (9:15) and Pharaoh (9:17) during the Exodus is a pattern repeated in Paul’s day, when a remnant of Israel is shown mercy (9:23-24) and the rest remains hardened (11:7, 25). Divine hardening does not cause a person to sin but is a disciplinary measure for those like Pharaoh who are already stubbornly resisting God (Ex 7:14; 8:15).