Abraham had been in the Land of Canaan for about twenty-four years (Genesis 12:4; cp. 17:1). During his pilgrimage there, he and his descendants were promised the land, where Abraham lived and walked. It would be theirs in due time. Abraham believed God, even when he had no descendant to inherit (Genesis 15:2-6). Nevertheless, Abraham had trouble understanding the context, in which God would do what he said he would do. It wasn’t until after God had introduced himself as Almighty God (Genesis 17:1) that the full impact of that context occurred to Abraham. For the very first time, he understood that he was unable to help God do, what he said he would do.
Abraham had done his very best to place himself in a position, where God could bless him. After discussing the matter with Sarah, she gave him Hagar, her handmaid, to be his concubine (Genesis 16:2), and Abraham produced Ishmael, his son (Genesis 15:15-16), in an effort to allow the Lord to bless him. Yet, the Lord rejected Ishmael and promised Isaac (Genesis 17:15-17) in their old age, when neither Abraham nor Sarah had the physical power to produce children. It was in the context of Almighty God (Genesis 17:1) that Abraham would have a child, through whom the grace of God would be fulfilled.
It appears that the three men wondered among themselves, where Abraham’s wife, Sarah, was (Genesis 18:9). No doubt they had seen her toiling at the hearth, as she prepared the bread, which they had eaten. Therefore, Abraham replied to their question, saying she was in the tent.[1] It was the Lord who, then, replied to Abraham, saying he would return again in the time of life (9 months), and Sarah would have a son, and Sarah, who had been listening at the door of her tent, heard what the Lord said (Genesis 18:10).
Understanding what this meant, since both she and her husband were beyond the age when they could have children, Sarah laughed at the thought (Genesis 18:11-12). It was then that the Lord placed Sarah’s behavior in context, when he asked: “Why did Sarah laugh, asking ‘Shall I really bear a child at my age” (Genesis 18:13; paraphrased)? And, the Lord added, “Is anything too difficult for the Lord?” Then the Lord repeated that he would, indeed return in 9 months and Sarah would have a child (Genesis 18:14.
It would seem that the Lord’s words were a rebuke against Abraham, not Sarah, as might be assumed. Just a short time earlier the Lord had told Abraham that Sarah would have a child, and he laughed, as well, at the thought of bearing a child at their ages (Genesis 17:17). While it seems evident from the text that Abraham had discussed the fact that Sarah and he had no children, although the Lord was insistent that Abraham would have a child (Genesis 16:1-6; cp. 15:5-6). It was agreed, as a result of that discussion, that Sarah’s handmaid, Hagar, would become Abraham concubine.
That said, however, there appears to have been no discussion over the fact that God told Abraham that he would have a son through Sarah, his wife (Genesis 17:17)! Abraham was so astonished at the fact, that he may have thought, telling Sarah what the Lord told him, might cause her to laugh at him in unbelief. It wasn’t a desirable thing in the traditions of the times for the husband to appear foolish in the eyes of his wife. Therefore, this may have been the reason for Abraham not discussing the matter of Isaac with her until now, because her reaction to what the Lord said certainly implies, she wasn’t told (Genesis 18:11-12). Moreover, hearing what was said, Sarah became afraid and denied she laughed, but the Lord rebuked her, saying she did, in fact, laugh (Genesis 18:15).
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[1] The text isn’t clear, but the fact that Sarah wasn’t present during the meal may have been pointed out as a subtle bone of contention against the traditions of men that kept women in submission. Of course, the Lord knew where Sarah was, so why bring up the fact that she wasn’t present, unless something wasn’t quite right about the event?
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