Abraham Serves Three Visitors Under the Oakby emmanuel_higgins

Genesis 18:13

And the LORD said unto Abraham, Wherefore did Sarah laugh, saying, Shall I of a surety bear a child, which am old?

The question belongs to the account in which heavenly messengers promised Abraham and Sarah that they would have the son Isaac. Sarah laughed because she disbelieved that she would surely bear a child when she was old, distrusting God's power to fulfill His promise, even while she and Abraham held that the promise would come true. She was reproved for that distrust.

Her laugh meant they did not wait in confiding faith for God to fulfill His promise of a son, but lacked faith and perfect trust in His power and failed to endure the test of faith in His unlimited power. In her doubt she looked to Hagar as the way the promise would be fulfilled, suggesting that Abraham take Hagar as wife, and Abraham listened to her voice, which brought much unhappiness upon himself and upon Sarah. The promise was given to prove Abraham's firm faith and reliance upon what had been promised to him.

The verse reveals God's unlimited power, with whom nothing is impossible, for He fulfilled His promise to Abraham and Sarah despite their old age. Their case proves what God can do and is to be remembered when a son is promised to another aged couple. Zacharias showed the same unbelief as Sarah when he doubted the angel's promise of a son through his wife well stricken in years, having forgotten this lesson for a moment, and failing to remember God's power in this way is forgetting Him and leads to unbelief.

The promise of the son was remembered when Abraham faced the command to offer Isaac. As part of the message of Genesis 18-19, the verse calls hearers to seek the Lord earnestly and take a decided stand, to be obedient to all of God's requirements rather than merely professing the truth, with confession of sin, earnest prayer, and hearts softened and subdued by the Spirit.