Summary: Focus on Abraham's faith and how we can consciously apply such faith to some area of life that is dependent upon God.
It began when he was 75. God’s first call to Abram came with a look into the future. "I will make you a great nation." (12:2-3). So Abram packed up and left, just as God told him to do. He arrived in Shechem, and once again God told him it was coming: "To your descendants I will give this land." (12:7) Descendants? That was looking less and less like a possibility. With the exception of his father Terah, the 8 generations before Abram all had their 1st child by age 32 on an average, and Abram is considering "Even Dad was 5 years younger when I was born."
-Then, in Canaan, God reminds him: (13:15-16) "I'll give this land to you and your descendants forever...I’ll make your descendants as innumerable as the dust." There’s that word again: descendants!
Ch 14, he goes on a rescue mission after his nephew Lot. Abram has "318 trained men," (14:14), all born in his household. But still the guy, whose name means "Exalted Father" has no child of his own. What a joke! What does Abram have? He has God’s promise, God’s reassurance that it’s all going to work out OK.
Finally, Abram asks, (Gen 15:2-4) "O Sovereign LORD, what can you give me since I remain childless and the one who will inherit my estate is Eliezer of Damascus?" And Abram said, "You have given me no children; so a servant in my household will be my heir. "Then the word of the LORD came to him: "This man will not be your heir, but a son coming from your own body will be your heir."
And then, like someone up in the crow’s nest of a ship who can look ahead and tell the others what’s coming up, God describes Abram’s future for him. He invites him outside for a look at the stars. "Count them. If you’re able. So shall your descendants be." And Abram puts his hands in his bathrobe pockets, takes a deep breath and says, "I believe it." It didn't matter that he was somewhere past the age of 75. Abram trusted God and in heaven his account gets a checkmark under the righteousness column. And God knows His creation. He knows that we’re helped by reassurances along the way, so He makes a covenant with Abram -- a solemn vow from God -- a contract with a seal. "Your descendants are going to possess this land, Abram."
Well, Abram believes God, but he’s not the only one involved in this picture. His wife Sarai is going to have a part in Abram’s child too! And Sarai seems less assured. Maybe she hadn’t been in on Abram’s conversations with God. Maybe Abram hadn’t done a very good job of sharing them with his wife. Maybe she’s just struggling, because the maternal time clock went off 30 years ago, and the thought of being a barren woman in her day was among the greatest of disgraces a woman could have. It’s been 10 years now since God’s promise. Sarai can’t take the waiting anymore. So, like we often do, she lays out a plan to help God along, since He isn’t getting it done well enough.
Ladies, the degree of her desperation is clear when she says to Abram, "This isn’t working. God’s not letting me have a child. Please, have sexual relations with my maid Hagar. Maybe we can have a child through her." So Sarai gives away intimacy with her husband that belonged to no one but her, to rush God along.