Translations
Sarah conceived and gave Abraham a son in his old age — born at the exact moment God had set — a child of promise, delivered precisely on time.
Sarah conceived and bore Avraham a son in his old age, at the appointed season that Elohim had spoken to him.
For Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him.
So Sarah conceived and bore a son to Abraham in his old age, at the very time God had promised.