Augustine of Hippo

Look and see that he alone is Father and his arm is the Son, and there are not two but one, a person and his arm. Not understanding or noticing how the words of one thing are transferred to other things on account of some similarity in everyday speech concerning visible and well-known things, how much more when ineffable things are spoken in some way, which are said in such a way to be impossible [in another way]? For a person calls another person "his arm" through whom he does whatever he does. And if he is taken away, he mourns and says, "I have lost my arm." And to the one who took him away, he says, "You have taken my arm away." We can thus understand how it can be said that the Son is the arm of the Father through which the Father works all things. Failing to understand this, we remain in the shadows of error, just like those of whom it was said, "To whom has the arm of the Lord been revealed?"