"Could you gaze into heaven five minutes, you would know more than you would by reading all that ever was written on the subject." (Joseph Smith, HC 6:2)

Joseph was not flaunting how great it was that HE knew, but was giving US an invitation. Closing the vision of the three degrees of glory, he reveals:

"But great and marvelous are the works of the Lord, and the mysteries of his kingdom which he showed unto us, which surpass all understanding in glory, and in might, and in dominion; Which he commanded us we should not write while we were yet in the Spirit, and are not lawful for man to utter; Neither is man capable to make them known, for they are only to be seen and understood by the power of the Holy Spirit, which God bestows on those who love him, and purify themselves before him; To whom he grants this privilege of seeing and knowing for themselves." (D&C 76:114-117)