18 But if this that you say is true—if it has been tested and thoroughly ascertained both that the gods boil with rage, and that an impulse of this kind agitates the divinities with excitement, on the one hand they are not immortal, and on the other they are not to be reckoned as at all partaking of divinity. For wherever, as the philosophers hold, there is any agitation, there of necessity passion must exist. Where passion is situated, it is reasonable that mental excitement follow. Where there is mental excitement, there grief and sorrow exist. Where grief and sorrow exist, there is already room for weakening and decay; and if these two harass them, extinction is at hand, viz. death, which ends all things, and takes away life from every sentient being.
Source: Against the Heathen (New Advent)