Most people don’t feel the need to struggle with Descartes over how they can be sure that they exist. And most don’t doubt the existence of the sun. These things are self-authenticating when one sees them.
And so is Jesus Christ.
He is the supreme I am (John 8:58). He is the “sunrise from on high” (Luke 1:78). He is the most self-authenticating Reality that exists.
But he must be seen. And he must be seen with true eyes, for which the eyes in our heads are but copies and shadows. Paul calls them the eyes of the heart in Ephesians 1:18 or the eyes of the mind in 2 Corinthians 4:4. These eyes are designed to see reality, what we call the truth. And they either see truth or, if the god…