We know that the Son of God has come, and has given us insight to know Him who is the Real God; and we are in Him who is real, even in his Son Jesus Christ. This is the real God, this is life eternal.
The unspiritual man rejects these truths of the Spirit of God; to him they are 'sheer folly,' he cannot understand them. And the reason is, that they must be read with the spiritual eye.