Resurrection of Jesus Christ 

The literal belief in the resurrection of Jesus' body, which later ascended into heaven, was a vital factor in the authority of the Catholic Church. (See "The Hiram Key" page 42)

Gnostic teachings called the literal view of of the resurrection 'the faith of fools' which seems to be supported by the secret traditions of Jesus' teachings. (See "The Hiram Key" page 42)

This is something that Christianity is based upon and that Christian 'believe' and 'know' to be the truth, with absolutely no proof of any kind.