Revelation

Logically, the best source of truth about God is God Himself. That is why revelation, or information given from God to a person, is so essential to true religion. One of my favorite set of verses from the Bible is James 1:5-6,

If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him.
But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed.

Isn't that a wonderful promise? God will give anyone wisdom liberally who asks for it sincerely.