Genesis 18:9

“And they said unto him, where [is] Sarah thy wife? etc.] One of them put the question; and so the Septuagint version renders it, “and he said unto him”, the principal of them, whom Abraham at first addressed and called him “my Lord”, and was no other than the Son of God in an human form; and various things in the context show him to be a divine Person, particularly his promise of return next year, and Sarah should have a son: and the question here put by him was not out of ignorance, for he who knew the name of Abraham’s wife, knew where she was; but this was asked in order to lead on to say something more concerning her, and that, hearing her name, she might draw nearer and listen to what…”

“- The Visit of the Lord to Abraham 2. השׂתחיה vayı̂śtachû “bow,” or bend the body in token of respect to God or man. The attitude varies from a slight inclination of the body to entire prostration with the forehead touching the ground. 6. סאה se'ah a “seah,” about an English peck, the third part of an ephah. The ephah contained ten omers. The omer held about five pints. This chapter describes Abraham’s fellowship with God. On the gracious assurance of the Redeemer and Vindicator, “Fear not, I am thy shield and thy exceeding great reward,” he ceased to fear, and believed. On the solemn announcement of the Conqueror of evil and the Quickener of the dead, “I am God Almighty; walk before me…”

“18:9 The visitors’ rhetorical question focuses attention on Sarah, whom the visitors knew by name.”