Today's reading covers the birth of Ishmael, the changing of Abram's name to Abraham, the Abrahamic covenant confirmed and made everlasting, and the promise of Isaac. There is a practical lesson concerning the birth of Ishmael. Rather than allowing God to work in His own time and way, Sarah ran ahead of God. This always brings trouble to our lives. The flesh always loves to "help" God, while true faith is shown in patience. Sarah doubted God's promise that she would bear Abraham a son. And Abraham ceased to walk in the Spirit and began to walk in the flesh. Someone has said, "Faith is living without scheming." We should never doubt God's promises. Remember, we cannot mix faith and flesh, law and grace, or promise and self-effort. As Christians, we must be strong and mature so that we might enjoy the fullness of God's perfect plan for our lives.