If we receive the witness of men, the witness of God is greater: for this is the witness of God which he hath testified of his Son. He that believeth on the Son of God hath the witness in himself: he that believeth not God hath made him a liar; because he believeth not the record that God gave of his Son. And this is the record, that God hath given to us eternal life, and this life is in his Son. He that hath the Son hath life; and he that hath not the Son of God hath not life. These things have I written unto you that believe on the name of the Son of God; that ye may know that ye have eternal life - 1 John 5
Belief in God is related to the subject to unending life, because God is the First Cause, has life within himself and freely gives unending life to his children. I personally have such a knowing not only of God, but of my eternal security in him....all born again Christians have this. And I agree, that it must be a bit unnerving to unbelievers.
Materialists are required to deny that anything can be known except through that which is collected through the 5 senses. Here's three non religious examples of revelation.
“In a dream I saw a table where all the elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper.” - DMITRI MENDELEEV, 1834 TO 1907 - Chemist who wrote the Periodic Table.
In 1903 Otto Loewi had the thought that nerve signals were possibly transmitted using chemical instructions. He could not think of how he could prove his new idea.
In 1920 Loewi had a dream about the problem. He woke excitedly during the night and scribbled notes about the dream.
In the morning, he could not remember the dream, and he could not read his nocturnal notes either!
The following night, he dreamed about the problem again. The dream was about an experiment he could use to prove his idea, and this time he remembered it.
He carried out research based on his dream and published the work in 1921, establishing that signalling across synapses was indeed chemical, as he had suspected.
The father of neuroscience, in 1936 was awarded the Nobel Prize in Medicine for work that came to him in a dream!
A revelation is proved true or not if the thing predicted comes true. Saving faith in Jesus Christ produces peace, and a number of other things promised in the NT. I have personally experienced this over the past 15 years or so. I have seen the same results in the half dozen or so other people I have led to Christ as well.
God is real, and can be known on a personal level ..... through "revelation".