11 “He ascended into heaven:” believe. “He sits at the right hand of the Father:” believe. By sitting, understand dwelling: as [in Latin] we say of any person, “In that country he dwelt (sedit) three years.” The Scripture also has that expression, that such an one dwelt (sedisse) in a city for such a time. Not meaning that he sat and never rose up? On this account the dwellings of men are called seats (sedes). Where people are seated (in this sense), are they always sitting?
Is there no rising, no walking, no lying down? And yet they are called seats (sedes). In this way, then, believe an inhabiting of Christ on the right hand of God the Father: He is there. And let not your heart say to you, What is He doing? Do not want to seek what is not permitted to find: He is there; it suffices you. He is blessed, and from blessedness which is called the right hand of the Father, of very blessedness the name is, right hand of the Father. For if we shall take it carnally, then because He sits on the right hand of the Father, the Father will be on His left hand. Is it consistent with piety so to put Them together, the Son on the right, the Father on the left? There it is all right-hand, because no misery is there.
Source: On the Creed: A Sermon to Catechumens (New Advent)