Romans 10 and 11 are about the "remnant of Israel". As clarified in chapter 9, "Israel" , "Jews" , "children of God" seem to refer to the "children of the promise" or "those of the faith of Abraham" , rather than the biological descendants of Abraham. Here, Paul speaks about how he longs for Israel to stop clinging to their own way of getting right with God by trying to keep the law. He longs for them to believe in what Christ has already accomplished in making them right with God. Paul asks a rhetorical question, "How can they believe in Him if they have never heard about Him?" (v.14). Paul says that not everyone who hears welcomes the message of the Good News. He explains, with quotes from Isaiah, that Israel not only heard, but understood the message. However, they rejected the message and kept disobeying and arguing against it. Paul says, though, that "not all the Jews have turned away from God", but a few are being saved as a result of God's grace in choosing them. "So this is the situation, that most of the Jews have not found the favor of God they are looking for so earnestly. A few have---the ones God has chosen-- but the rest were made unresponsive" (v. 11:7). The "Jews" are God's chosen people and are the objects of His promises to Abraham, for God's gifts and his call can never be withdrawn (v.29). Paul then says to the gentiles, "you ,too, were once rebels against God, but when the Jews refused his mercy, God was merciful to you instead. And now, in the same way, the Jews are the rebels, and God's mercy has come to you. But someday they , too, will share in God's mercy (v.31)". There is much to cause confusion in all of this, but that's ok. "Oh, the depth of the riches of the wisdom and knowledge of God! (v.33)" Maybe it is impossible for us to understand all the details, but it's enough just to know that "everything exists by his power and is intended for His glory" (v.36).