Proslogium and Monologium/Monologium/Chapter13

Chapter XIII
As all things were created through the supreme Being, so all live through it.

It is certain, then, that through the supreme Nature whatever is not identical with it has been created. But no rational mind can doubt that all creatures live and continue to exist, so long as they do exist, by the sustenance afforded by that very Being through whose creative act they are endowed with the existence that they have. For, by a like course of reasoning to that by which it has been gathered that all existing beings exist through some one being, hence that being alone exists through itself, and others through another than themselves -- by a like course of reasoning, I say, it can be proved that whatever things live, live through some one being; hence that being alone lives through itself, and others through another than themselves.

But, since it cannot but be that those things which have been created live through another, and that by which they have been created lives through itself, necessarily, just as nothing has been created except through the creative, present Being, so nothing lives except through its preserving presence.