When God told Abraham he would have a son with Sarah, this was his response.
“Then Abraham fell on his face and laughed and said to himself, “Shall a child be born to a man who is a hundred years old? Shall Sarah, who is ninety years old, bear a child?” And Abraham said to God, “Oh that Ishmael might live before you!” Genesis 17:17-18
Interesting how the father of faith laughed when God told him about having a son with Sarah. Later, Sarah does the same thing when she hears that she is going to have a child.
“So Sarah laughed to herself, saying, “After I am worn out, and my lord is old, shall I have pleasure?” The Lord said to Abraham, “Why did Sarah laugh and say, ‘Shall I indeed bear a child, now that I am old?’” Genesis 18:12-13
When you think about it, is kind of funny. To old people—I mean REALLY OLD PEOPLE—Having a child together in the NATURAL, with a little supernatural, help, kind of way. No wonder why God took it upon Himself to name the child. What would that name be? What else could it be? He laughs! That is what the Hebrew name Yitzchak (Isaac) means. Anyone who hears this story will think of two things: One, God has a sense of humor, and two, nothing is too hard for Him to accomplish. (Genesis 18:14)
Of course, exactly when God predicted, the promised child arrived.
“The Lord visited Sarah as he had said, and the Lord did to Sarah as he had promised. And Sarah conceived and bore Abraham a son in his old age at the time of which God had spoken to him. Abraham called the name of his son who was born to him, whom Sarah bore him, Isaac.” Genesis 21:1-3
So, are you praying for something in earnest? Have you given up? Don’t do so! Get ready to laugh and realize that with God, nothing is impossible. (Mark 10:27; Romans 8:31; Mark 11:22-25)