Genesis 17:15 - Meaning and Application

Here, God promises Abraham a son by Sarai, the one through whom the promise to make him the father of many nations would be fulfilled. Sarah also would become a mother of nations, and kings of peoples would come from her (Genesis 17:16). God reveals his good plans to his people little by little. He had told Abraham long before that he would have a son, but not until now that the son would come through Sarai.

The Lord’s blessing brings fruitfulness and no sorrow with it, unlike Hagar’s case. God says, in effect, that he will bless Sarah with fruitfulness, and then Abraham will have a son by her. Civil order and rule are also a great blessing to the church. The promise is not only of people, but of kings of peoples, a well-ordered society, not a scattered crowd.

This promise is confirmed by the change of Sarai’s name to Sarah (Genesis 17:15). A letter is added to her name, just as it was to Abraham’s, for the same reasons. Sarai means “my princess,” as if her honor belonged to only one family. Sarah means “princess,” that is, a princess of many, and points to the Messiah, the Prince, even the prince of the kings of the earth.

Abraham welcomes this gracious promise with joy and thankfulness (Genesis 17:17). He falls on his face, showing deep humility. The more honor and favor God gives us, the lower we should feel in our own eyes, and the more reverent we should be before him. He also laughs, and this is a laugh of delight, not disbelief. The promises of a holy God, as well as his acts, are the joy of holy people; there is joy in faith as well as joy in receiving.

At this point Abraham rejoiced to see Christ’s day. He saw it and was glad (John 8:56). He saw heaven in the promise of Canaan, and Christ in the promise of Isaac. He also marvels at the promise, asking whether a child can be born to a man who is a hundred years old. He is not doubting the promise, for he did not weaken in faith (Romans 4:20). Rather, he is amazed at what only God’s almighty power could do, and at how kind God is to make the gift so surprising and moving (Psalm 126:1-2).

Abraham then prays for Ishmael: “Oh that Ishmael might live before you!” (Genesis 17:18). He does not mean that Ishmael should be preferred over the son Sarah would bear. Rather, he fears that Ishmael may be left out and abandoned by God, so he pleads for him. Since God is speaking with him, Abraham sees a good opportunity to speak a word for Ishmael, and he does not miss it. We should not tell God what to do, but he does allow us to be open and specific in prayer (Philippians 4:6). Whatever troubles us should be laid before him.

It is also a parent’s duty to pray for children, all of them. Job did this, offering burnt offerings according to the number of all his children (Job 1:5). Abraham does not act as if Ishmael were forgotten now that God has promised him another son by Sarah. No, he still carries Ishmael on his heart. The hope of new blessings should not make us forget old ones. The greatest thing we should ask for our children is that they may live before God, meaning that they stay in covenant with him and walk uprightly before him. Spiritual blessings are the best blessings, and we should earnestly seek them for ourselves and others. Those live well who live before God.

God answers Abraham’s prayer with peace. Abraham does not seek God’s face in vain. Common blessings are secured to Ishmael (Genesis 17:20). God says, in effect, “As for Ishmael, whom you care so much about, I have heard you.” Ishmael will enjoy favor for Abraham’s sake, and God has blessings stored up for him. His descendants will be many, and he will multiply greatly, more than his neighbors. This is the fruit of blessing, as in Genesis 1:28. They will also become important, for twelve princes will come from him. We may kindly hope that Ishmael also received spiritual blessings, though the visible church did not come through him and the covenant was not placed in his line. Often, children born after the flesh receive much outward good for their godly parents’ sake.

But covenant blessings are kept for Isaac and given to him alone (Genesis 17:19, 17:21). If Abraham wanted the covenant to pass through Ishmael, God does not answer him in those exact terms, but in something just as good, even better. God repeats the promise that Sarah herself will bear Abraham a son. True believers still need God’s promises repeated to them, so they may have strong comfort (Hebrews 6:18). Children of promise are truly children indeed.

God also names the child Isaac, which means “laughter,” because Abraham rejoiced when the son was promised. If God’s promises are our joy, then the mercy promised will become our great joy in time. Christ will be joy to those who wait for him. Those who now rejoice in hope will soon rejoice in what they hoped for, and this is a joy that is not foolish. God also establishes his covenant with Isaac. God takes whom he pleases into covenant with himself, according to the good pleasure of his will (Romans 9:8, Romans 9:18). So the covenant was settled between God and Abraham with its limits and remaining promises, and then the meeting ended. God stopped speaking with him, and the vision disappeared. The Lord went up from Abraham. Our fellowship with God here is broken and interrupted, but in heaven it will be constant and never ending.