For the Scripture says to Pharaoh, “For this very purpose I have raised you up, that I might show my power in you, and that my name might be proclaimed in all the earth.”  So then he has mercy on whomever he wills, and he hardens whomever he wills.
This is all about glorifying God. God was in control then as he is now and as he will always be. God allowed Pharaoh to pursue what was natural to him – a hardened heart. God was later glorified in later displaying his power against Pharaoh. Conversely God will show mercy when there should be none, to whom he wills, further glorifying him. In either case God is glorified.
As Christians living our lives to glorify God and with open hearts filled with the Spirit, we won’t be treated like that where God hardened Pharaoh’s heart and used his wrath to his glory.
We are called to live our lives to glorify God. So, whether you eat or drink, or whatever you do, do all to the glory of God. (1 Cor 10:31, ESV) Given that we do indeed to that, God will use us to glorify him with his mercy, even in our pain.
Lord I love you. Thank you for choosing me. Thank you for my salvation and for filling my heart with your Spirit. I pray I glorify you in all I do. In Jesus’ holy name I pray, amen.