“The Lord remembered Sarah as He had said, and the Lord did to Sarah as He had spoken” (Genesis 21:1). “The Lord remembered Sarah as He had said.” That is what the verse said: “All the trees of the field will know that I, the Lord, have lowered a high tree, elevated a lowly tree” (Ezekiel 17:24) – Rabbi Yudan said: Not like those who speak but do not act, but rather, “I, the Lord, have spoken and acted” (Ezekiel 17:24).
Where did He speak? “At the prescribed time, I will return to you… and Sarah will have a son” (Genesis 18:14); and He acted. “All the trees of the field will know” – this refers to people, as it says: “For man is the tree of the field” (Deuteronomy 20:19). “That I, the Lord, have lowered a high tree” – this refers to Avimelekh.
“Elevated a lowly tree” – this refers to Abraham. “Dried a moist tree” (Ezekiel 17:24) – this refers to Avimelekh’s wives. “Caused a dry tree to blossom” (Ezekiel 17:24) – this refers to Sarah. “I, the Lord, have spoken” – where [in Scripture] did He speak?
“At the time, I will return to you.” “And acted” – that is what is written: “And the Lord did to Sarah as He had spoken.”