But as it is written, Eye has not seen, nor ear heard, neither have entered into the heart of man, the things which God has prepared for them that love Him. But God has revealed them to us by His Spirit: for the Spirit searches all things, yes, the deep things of God.
For what man knows the things of man, except the spirit of man which is in him? even so the things of God know no man, but the Spirit of God.
Now we have received, not the spirit of the world, but the spirit which is of God; that we might know the things that are freely given to us of God. Which things also we speak, not in the words which man's wisdom teaches, but which the Holy Ghost teaches; comparing spiritual things with spiritual things. (1 Cor. 2:9-13)