Sincerity of Belief....

“Eve really believed the words of Satan, but her belief did not save her from the penalty of sin. She disbelieved the words of God, and this was what led to her fall. In the judgment men will not be condemned because they conscientiously believed a lie, but because they did not believe the truth, because they neglected the opportunity of learning what is truth. Notwithstanding the sophistry of Satan to the contrary, it is always disastrous to disobey God. We must set our hearts to know what is truth.”

Patriarchs and Prophets, p 56

You can read Patriarchs and Prophets by Ellen G. White online at - http://www.whiteestate.org/books/pp/pp.asp