More precisely, infinite regress here can mean two things:

The first is an infinite regress in action as such.

The second is an infinite regress in performing a particular act.

The first means that He does not bring anything whatsoever into existence until He brings something into existence. The statement thus amounts to saying that He does not create until He creates, does not act until He acts, and does not bring anything into existence until He brings something into existence. This is necessarily impossible.

This is, in fact, circularity rather than an infinite regress, since it means that a thing cannot exist until it exists. This entails combining two contradictories: if it does not exist until it exists, it must be both nonexistent and existent.

But suppose it is said:

“He performs no act without a condition concurrent with it, and He brings about that condition only with a condition concurrent with it.”

This is an infinite regress in what completes causal efficacy, not an infinite regress of successive things. This, then, is an infinite regress in what completes causal efficacy, whereas the first is an infinite regress in the very basis of causal efficacy. Both are impossible.

The first is what should be meant by the statement:

“If He did not act and then acted, something must have come into existence: a power, a will, knowledge, or something else.”

The same argument concerning how the first thing comes into existence then applies to how this comes into existence. For this second thing, too, comes into existence only when something else comes into existence alongside it. Whatever is needed to complete causal efficacy must be present when the effect is produced; its prior existence is not enough.

Accordingly, this argument can be formulated in two ways:

The first is to say:

“He does not bring anything into existence until He brings something into existence, and He does not do anything