Now the LORD was gracious to Sarah as he had said, and the LORD did for Sarah what he had promised.
Genesis 21:1
This verse pictures the joy of fulfillment. At last we have two sons of Abraham living side-by-side, Isaac and Ishmael. We don't need to wonder what this means in the life of faith, because in Galatians 4, Paul tells us. He says that Isaac is a picture of that which is born of the Spirit, and Ishmael is a picture of that which is born of the flesh. Isaac is the result of a life controlled by the Spirit. What does that mean to us? In that same letter he tells us, the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control
(Galatians 5:22-23a). These are the Isaacs for which we have been waiting. Ishmael, on the other hand, stands for the works of the flesh that are outlined in that very same chapter. Notice how that is confirmed in this passage. First, Isaac's birth was supernatural. He was not born until Abraham and Sarah had reached an advanced age. Sarah was ninety years old, and Abraham was one hundred. It occurred at the set time, some thirty years after God had first promised to give Abraham a son. In Romans 4:19a, Paul refers to this time and says, Without weakening in his faith, he faced the fact that his body was as good as dead—since he was about a hundred years old—and that Sarah's womb was also dead.
This was a supernatural birth, where God quickened the natural processes again and a child was born.
Do you see now why God waited all this long time to fulfill the promise to Abraham? He was waiting until the ability and forces of natural man had ceased so His promise could definitely be a supernatural fulfillment. This is exactly what God says to us about the fruit of the Spirit in our lives. It will never come from the flesh. It will never come from self-effort or by positive thinking or by perpetual trying. Love, joy, and peace—those wonderful gifts of God—never come from any attempt on our part to imitate them. You can imitate them, but they will never be anything but an imitation. You cannot produce the fruit of the Spirit by the flesh, because that fruit is the supernatural gift from the life lived in the power of the Spirit of God, born as Isaac was here.
Lord, I see both Isaac and Ishmael within me. Produce in me those Isaac-like qualities that I cannot generate in myself.
Life Application
Are we trying our best to imitate the nourishing and life-giving fruit that can be produced only by God's Spirit? Do we see the difference between trying and trusting?