The Salvation of Israel's Remnant
"Isaiah cries out concerning Israel: 'Though the number of the sons of Israel be as the sand of the sea, only a remnant of them will be saved, for the Lord will carry out his sentence upon the earth fully and without delay.'"
Ultimately, election and reprobation are two of Christianity's greatest mysteries, truths God has revealed in part without telling us everything we might like to know about them. The difficulty of election and reprobation means we should handle these teachings with care. Moreover, in order that we might defend these doctrines, we should know the common misunderstandings of them, including the views of election as arbitrary and reprobation as shutting the doors of heaven to people who want to be there. Our answer is that although God does not elect people to salvation based on anything they have done or will do, He has a (not fully revealed) purpose in election (Rom. 9: 10-13). Paul also notes that the Lord draws the reprobate from the same fallen lump of clay as the elect (vv. 21-24); therefore, reprobation is not His standing in the way of people who want to be with Him. He gives the reprobate what they want, for the perverse reality of sin is that unless God intervenes, fallen people prefer His wrath over seeing Him in heaven (1:18-32; 3:9-18; Rev. 22:11).
Another common misunderstanding of divine election is that the Lord elects only a group to salvation, that God chooses to save the invisible church without choosing the individuals who will belong to it. Our response must be brief. First, groups do not exist apart from their individual members. The Lord cannot finally choose to save a group without choosing its members. Moreover, we again note that the objections Paul answers in Romans 9 make sense only if the election of individuals is in view. What seems "unfair" about God's choosing to save a particular group if my membership in that group finally depends on me?
Divine election of individuals to salvation reveals the Lord's mercy in preserving a remnant of ethnic Israelites out of a fallen, undeserving people. It shows the elect's utter dependence on God; without His grace, Israel's fate would be complete annihilation (Rom. 9:27-29). But the Lord has also elected a remnant of Gentiles, fulfilling Hosea 1:10 and 2:23 (Rom. 9:25-26). Hosea originally spoke of the restoration of ethnic Israelites, but Paul fittingly applies it to Gentiles. In Hosea's day, the Israelites had broken their covenant with the Lord so completely that they had made themselves unclean Gentiles, spiritually speaking. Paul sees that saving such Israelites is not essentially different from redeeming Gentiles who have never known the God of Israel. Redeeming Israelites-turned-Gentiles as well as naturally born Gentiles means saving those outside God's covenant.
Coram Deo
God continues to save people who, having been in covenant with Him, sin gravely and put themselves out of the visible covenant community via excommunication. The Lord promises that no matter what we have done, He is faithful and just to forgive us our sins when we repent and believe the gospel (1 John 1:8-9). If you have put yourself outside of God's visible church by your sin, know that the Lord is willing and waiting to forgive you when you repent.