Romans 9

http://www.esvbible.org/Romans+9/

Paul says that he wishes, after living as a Christian, that things could go back to the way they were before when the Jewish people were automatically God's children through the first covenant. Life would be so much easier on him, since he was born Jewish. Now, God's children are those He chooses, and He choses those who put their faith in His Son Jesus. God gave Abraham a son in his old age when it shouldn't have been possible. When Isaac had his sons by Rebekah, God told Rebekah that her older son would serve the younger son. God made this so because He wanted to show that His plans are always dominant. In those times, the oldest son was the most important, but God wanted to say that the way humans thought things should be did not matter to Him. The Jewish people all came from that younger son, Jacob, so God proved He can choose who He wants. God made you in the exact way that you are supposed to be. Don't come to Him and point out things that aren't the way they're supposed to be. How can the created talk back to the creator. God can refine you, but He has made you how you are supposed to be.

Paul quotes the prophets, who wrote hundreds of years before Jesus that those who were not the chosen ones will become God's children, and although the descendants of Abraham are as numerous as the grains of sand on the shore, few of them will be saved in the end. Many of those who have found salvation through Christ are non-Jewish people who weren't looking to please God. But they found that they needed to place their faith in Jesus. Many of the Jewish people looked to please God by obeying Moses' Laws, but the corrupt nature keeps them from doing so, and they did so instead of placing their faith in Christ.