Whilst there are thus many gods and lords, whereof some are such in reality, and others are such only in name, we strive to rise not only above those whom the nations of the earth worship as gods, but also beyond those spoken of as gods in Scripture, of whom they are wholly ignorant who are strangers to the covenants of God given by Moses and by our Saviour Jesus, and who have no part in the promises which He has made to us through them. That man rises above all demon-worship who does nothing that is pleasing to demons; and he rises to a blessedness beyond that of those whom Paul calls “gods,” if he is enabled, like them, or in any way he may, “to look not at the things which are seen, but at the things which are unseen.”
And he who considers that “the earnest expectation of the creature waits for the manifestation of the sons of God, not willingly, but by reason of him who subjected the same in hope,” while he praises the creature, and sees how “it shall be freed altogether from the bondage of corruption, and restored to the glorious liberty of the children of God,” — such a one cannot be induced to combine with the service of God the service of any other, or to serve two masters. There is therefore nothing seditious or factious in the language of those who hold these views, and who refuse to serve more masters than one.
To them Jesus Christ is an all-sufficient Lord, who Himself instructs them, in order that when fully instructed He may form them into a kingdom worthy of God, and present them to God the Father. But indeed they do in a sense separate themselves and stand aloof from those who are aliens from the commonwealth of God and strangers to His covenants, in order that they may live as citizens of heaven, “coming to the living God, and to the city of God, the heavenly Jerusalem, and to an innumerable company of angels, to the general assembly and Church of the first-born, which are written in heaven.”
Source: Against Celsus (New Advent)