This is the Argument from Truth as it appears on Peter Kreeft's website.
11. The Argument from Truth
This argument is closely related to the argument from consciousness. It comes mainly from
1. Our limited minds can discover eternal truths about being.
2. Truth properly resides in a mind.
3. But the human mind is not eternal.
4. Therefore there must exist an eternal mind in which these truths reside.
This proof might appeal to someone who shares a Platonic view of knowledge—who, for example, believes that there are Eternal Intelligible Forms which are present to the mind in every act of knowledge. Given that view, it is a very short step to see these Eternal Forms as properly existing within an Eternal Mind. And there is a good deal to be said for this. But that is just the problem. There is too much about the theory of knowledge that needs to be said before this could work as a persuasive demonstration.