For God’s gifts and His call are irrevocable.
Romans 11, 29

This is the way our earthly courts work: you can appeal a decision and go to the next institution. But at some point you are in the last institution, and the judgment becomes final and irrevocable. No further appeals are possible.
This is how God’s judgment works: after death we come before the holy, incorruptible, just Judge. As He decides, so will our eternity be. There is no more probation and no more appeal. If you have lied just once, you are a liar who cannot go to heaven. Unless you have an advocate, Jesus Christ. When Jesus intercedes for you, He says: He may have lied, but I atoned for him on the cross. The punishment is completed, he is free! – And the lie and all other sins are erased from the book of God and from His memory and forgotten; – irrevocably.
So it is with Israel, which is actually the subject of this verse: God once said Yes to this people, He once adopted them as His own. And HE never lets His people fall again. Israel has often rebelled against God and has​ ​devoted itself to the Law instead of the person of God.  It has rejected the Redeemer and Messiah, but God does not reject His people forever. Israel still belongs to the LORD, even though it is now going its own way.
This is how it is with us: irrevocable is the grace that God has with us: We are His beloved children, if Jesus has made us so. Irrevocable is our calling to Jesus. Once we have followed Jesus as the King of our hearts, the calling to God’s Kingdom remains forever. HE is God and not man, so He never has anything to repent of, HE is faithful and reliable and does not say yes today and no tomorrow.
So someone who has accepted Christ as Saviour may go astray: God is patient and faithful. One may even go astray and praise others as gods: God is still patient and faithful and accompanies His child. His patience is much greater than ours. We would condemn the erring, He would not. Let us learn from the love, faithfulness and patience of God, let us not condemn ourselves or others!

Thank You Jesus, You are faithful to me. Your calling is still for me: to be a child of God. Forgive me if I find myself on a detour or go astray, and bring me home safely! Yes, I will follow You alone, for Your grace is irrevocable!