Proof of God's existence is given by the fact that anyone asks whether He exists.
What is the smallest knowable piece of information? I find this consideration a most worthy thought exercise. There are several closely related questions:
Then Moses asked God, “If I go to the Israelites and say to them: The God of your fathers has sent me to you, and they ask me, ‘What is His name? ’ what should I tell them? ” God replied to Moses, “I AM WHO I AM. This is what you are to say to the Israelites: I AM has sent me to you.”
It is an exceedingly beautiful and wondrous paradox: that the sovereign God of the universe has called us not unto blind, rote, or automatic conformity with His will, but unto willing obedience and submission to His will, which we cannot do without His help.