I Samuel 3:2, 7, 9

And it came to pass at that time, while Eli was lying down in his place, and when his eyes had begun to grow so dim that he could not see

(Now Samuel did not yet know the LORD, nor was the word of the LORD yet revealed to him.)

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