Now we, brothers and sisters, as Isaac was, are children of promise. (Galatians 4:28)
… just as Abraham “believed God, and it was accounted to him for righteousness.” Therefore know that only those who are of faith are sons of Abraham. (Galatians 2:6-7)
St Paul calls us Christians “children of the promise.” We are children of the promise God made to Abraham because we too believe God, as Abraham did and so are the rightful children of Abraham: not according to the flesh, but according to faith. Biblical scholar Terence E. Fretheim comments on what it means that God makes a promise to humans:
“As in any relationship of integrity, God will have to give up some things for the sake of the relationship. Thus, God will have to give up some freedom. Any commitment or promise within a relationship entails a limitation of freedom. By such actions, God has decisively limited the option God has for speaking and acting. God has exercised divine freedom in making such promises in the first place. But, in having freely made such promises, thereafter God’s freedom is truly limited by those promises. God will do what God says God will do; God will be faithful to God’s own promises, and that is a limitation of freedom. God’s freedom is not most supremely a freedom for the world, not a freedom from the world.
[As Fretheim notes as soon as God makes a promise God is committed to following the course of action that will bring the promise to fruition. This means God can’t ignore the promise, nor can God change His will and pursue other ideas instead. Thus, in making a promise God commits Himself to a course of action and history which in effect limits God’s freedom. In promising us something God is imposing some limits on Himself. In tying His promise to our behavior, God enters into a synergistic relationship with humans and ties His own will and activity to ours. God vows to work in, through and with us humans to accomplish His will.]
Moreover, any relationship of integrity will entail a sharing of power. Each party to the relationship must give up any monopoly on power for the sake of the relationship. Neither party to the relationship can be overwhelmed for the relationship to be a true one. For the sake of the relationship, God gives up the exercise of some power. This will in turn qualify any talk about divine control or divine sovereignty. Total control of the other in a relationship is no relationship of integrity.” (The Suffering of God: An Old Testament Perspective, pgs. 36-37)
In other words, God continues to respect our human free will and does not endeavor to take it away from us or declare it of no value. Rather in making us children of the promise, God also promises to work with us for our salvation.