Ante-Nicene Fathers, Vol VII:
Lactantius: Chap. II.—That there is but one God, and that there cannot be more

Chap. II.—That There is But One God, and that There Cannot Be More.

Another question follows: Whether there be one God or more? And this indeed contains much ambiguity. For not only do individuals differ among themselves, but also peoples and nations. But he who shall follow the guidance of reason will understand that there cannot be a Lord except one, nor a Father except one. For if God, who made all things, is also Lord and Father, He must be one only, so that the same may be the head and source of all things. Nor is it possible for the world 1449 to exist unless all things be referred to one person, unless one hold the rudder, unless one guide the reins, and, as it were, one mind direct all the members of the body. If there are many kings in a swarm of bees, they will perish or be scattered abroad, while  

If there are several leaders in a herd, they will contend until one gains the mastery. 1451 If there p. 225 are many commanders in an army, the soldiers cannot obey, since different commands are given; nor can unity be maintained by themselves, since each consults his own interests according to his humours. 1452 Thus, in this commonwealth of the world, unless there were one ruler, who was also its founder, either this mass would be dissolved, or it could not have been put together at all.  

Moreover, the whole authority could not exist in many deities, since they separately maintain their own duties and their own prerogatives. No one, therefore, of them can be called omnipotent, which is the true title of God, since he will be able to accomplish that only which depends upon himself, and will not venture to attempt that which depends upon others. Vulcan will not claim for himself water, nor Neptune fire; nor will Ceres claim acquaintance with the arts, nor Minerva with fruits; nor will Mercury lay claim to arms, nor Mars to the lyre; Jupiter will not claim medicine, nor Æsculapius the thunderbolt: he will more easily endure it when thrown by another, than he will brandish it himself. If, therefore, individuals cannot do all things, they have less strength and less power; but he is to be regarded as God who can accomplish the whole, and not he who can only accomplish the smallest part of the whole.  

Footnotes

Rerum summa.  

Virg., Georg., iv. 68.  

Obtineat.  

Pro moribus. Another reading is “pro viribus,” with all their power.