Concerning the Nature of Good, Against the Manichæans

Therefore now by common usage things small and mean are said to have measure, because some measure remains in them, without which they would no longer be moderate-sized, but would not exist at all. But those things that by reason of too much progress are called immoderate, are blamed for very excessiveness; but yet it is necessary that those things themselves be restrained in some manner under God who has disposed all things in extension, number, and weight.