1 Samuel 3:9-10

New King James Version

⁹ Therefore Eli said to Samuel, “Go, lie down; and it shall be, if He calls you, that you must say, ^(A)‘Speak, Lord, for Your servant hears.’ ” So Samuel went and lay down in his place.

¹⁰ Now the Lord came and stood and called as at other times, “Samuel! Samuel!”

And Samuel answered, “Speak, for Your servant hears.”