It is not as though the word of God had failed. For not all Israelites truly belong to Israel, and not all of Abraham's children are his true descendants; but "It is through Isaac that descendants shall be named for you." This means that it is not the children of the flesh who are children of God, but the children of the promise are counted as descendants. ...something similar happened to Rebecca when she had conceived children by one husband, our ancestor Isaac. Even before they had been born or had done anything good or bad (so that God's purpose of election might continue, not by works but by his call) she was told, "The elder shall serve the younger." -- Romans 9:16-13
Chapters 9 through 11 of Paul's letter to the Romans have often been used by Christians to exclude Jews from God's kingdom. But Paul is not making a distinction between Jews and Christians, he is making a distinction between those who believe in God's promise and those who do not. Both Jews and Gentiles could be children of the promise. This distinction did not depend on their DNA, their parentage, their flesh. It all depended on whether they believed in God's promise: that nothing could separate them from the love of God. (See Romans 8:38-39).
Paul uses the example of Jacob and Esau to illustrate his point. Both Jacob and Esau were born of Rebecca and Isaac. Twins, no less. But Esau did not value his birthright, while Jacob did.
Why does God separate his children into factions? We are told that God hardens the heart of some people. So, they don't seem to have a choice in the matter. They are simply unable to believe that God is doing something new. Why?
Perhaps, God is testing those who do believe. What have those who believe in God's promise learned about God? How, for example, do we (assuming we are chosen) respond to those who are hardhearted, who cannot accept that God's love and forgiveness is for everyone? Do we love them?
Do we appreciate God's saving grace to us, know that it is undeserved, and so treat everyone as gracefully as God treats us? Or, do we become proud of ourselves, our "election", and judgmental towards others? Do we think we are better, more righteous, than the ones who stumble? Do we become hardhearted ourselves?
Paul says (I paraphrase), Note then God's kindness towards you, provided you continue in his kindness; otherwise you will be cut off too. (9:22) Paul seems to be saying that we have a choice to be kind to everyone, or be cut off. Our choices matter. God loves all of us, though only some choose to accept this. We can be hardhearted, or, we can choose to be kindhearted (even to the hardhearted!), mirroring God's love.
I am reminded of Keisha Thomas, a young black girl who was amongst a group of protesters at a KKK rally in Michigan in 1996. When her fellow protesters saw a man at the rally wearing a Confederate flag on his shirt, and started to physically attack him, Keisha stepped in front of her friends, and shielded the man with her body. Her response when asked why she had done this was, "Beating someone won't change their mind." (http://www.people.com/people/archive/article/0,,20141729,00.html) Only kindness will change, soften, people's hearts -- the kindness that Christ lived, and died trying to share. The leader of the KKK rally later said "We bless her." That's pretty amazing, isn't it?
Getting back to Jacob and Esau.... How did Jacob respond to Esau when he saw him again after twenty years? Had Jacob learned anything during his separation from his family? Did he still want to take from his brother what belonged to him? No. Jacob was a completely changed man. He instead tried to give everything he had gained to his brother in order to soften his brother's heart.
Dear God, I know that nothing will separate me from your love. Please help me to keep in mind that this has nothing to do with me, and everything to do with you. Please keep my heart soft towards all people. Love always, Pam