Describe the encounter between Richard and Darken Rahl in the Garden of Life at the end of the book?

Darken Rahl offers Richard Immortality and the life of Kahlan if he will help to free the Keeper. When Richard refuses Darken Rahl shows a vision of Kahlan being beheaded and tells him that either she dies or the Keeper is freed. Richard realizes this is what the prophecy meant and he can't free Kahlan and sentence the entire world to death. Richard defeats Darken Rahl sending him back to his prison and putting the Stone of Tears back on the Keeper's prison.