For “although there be that are called gods” in name, “whether in heaven or in earth, yet to us there is but one God the Father, of whom are all things;” whence the greater reason why, in our view, that which is the property of God ought to be regarded as pertaining to God alone, and why (as I have already said) that should cease to be such a property, when it is shared by another being. Now, since He is God, it must necessarily be a unique mark of this quality, that it be confined to One. Else, what will be unique and singular, if that is not which has nothing equal to it? What will be principal, if that is not which is above all things, before all things, and from which all things proceed? By possessing these He is God alone, and by His sole possession of them He is One. If another also shared in the possession, there would then be as many gods as there were possessors of these attributes of God.
Tertullian
Against Hermogenes
Chapter IV