Hi Rolf, as far as I can tell, no one except me, posting of this thread has a clue as to what a conditionalist believes. At issue is the traditional belief that once a sinner is thrown into the lake of fire, he or she undergoes eternal conscience torment, versus those who say once God's perfect justice is satisfied, the person's conscience awareness ends, their body and soul being destroyed (killed.)
The key verse in this debate is Revelation 14:11, ""And the smoke of their torment goes up forever and ever; they have no rest day and night, those who worship the beast and his image, and whoever receives the mark of his name."
It is easy to see why the traditional view arose, seemingly the smoke rising forever and ever points to ongoing torment forever and ever. But another option is that the smoke rising forever and ever simply indicates the eternal consequence of being tormented in the lake of fire, eternal separation from God.