This is pretty clear. The word of the LORD is a person! Messages or sounds don’t come and stand. What was it that the apostle John said? “In the beginning was the word and the word was with God and the word was God.” I think Samuel is being visited by the pre-incarnate Jesus. The same thing happened to Abraham and it is the reason Jesus could say, “Your father Abraham rejoiced at the thought of seeing my day; he saw it and was glad.” They replied, “You are not yet fifty years old and you have seen Abraham?” Jesus answered, “Before Abraham was born, I am.”
The unity of scripture always amazes me. Let’s keep exploring it together.