How does Descartes arrive at the conclusion that the idea of God is the most clear and distinct

Question

He says that God cannot be materially false because God is the most clear and distinct of all his ideas in his mind.

But why was he able to say that his idea of God is the most clear and distinct of all his ideas?

i think it has something to do with the formal and objectives realities which he mentions. (and which i don't understand)

Answer 1

Our idea of God contains (symbolically) infinite perfection.  Since we are not perfect, we can't be the cause of this idea.  Only something infinitely perfect could have caused it.  Therefore, only God could have caused it since only God is infinitely perfect.