10 It is no god, you will say; because it is the tutelary genius of Carthage. As though if it were Mars or Mercury, it would be a god. But consider in what light it is esteemed by them; not what it is in itself. For I know also as well as you, that it is but a stone. If this “genius” be any ornament, let the citizens of Carthage live well; and they themselves will be this “genius” of Carthage. But if the “genius” be a devil, you have heard in that same Scripture, “The things which the Gentiles sacrifice, they sacrifice to devils, and not to God; and I would not that you should have fellowship with devils.” We know well that it is no God; would that they knew it too!
But because of those weak ones who do not know it, their conscience ought not to be wounded. It is this that the Apostle warns us of. For that they regard that statue as something divine, and take it for a god, the altar is witness. What does the altar there, if it be not accounted a god? Let no one tell me; it is no deity, it is no God. I have said already, “Would that they only knew this, as we all do.” But how they regard it, for what they take it, and what they do about it, that altar is witness. It is convincing against the intentions of all who worship there, grant that it may not be convincing also against those who sit at meat with them!
Source: Sermons on Selected Lessons of the New Testament (New Advent)