This seems to be one of the many problems, when it comes to faith and several types of religions - especially Islamic beliefs & Christianity. Thinking about "Doomsday" and "Armageddon" proves, once again, how dangerous organized religions are.
By the way, this is an infinite existence - so the "when will the world end" query doesn't apply in actuality; life is going on throughout the cosmos and isn't limited to planet Earth. Life also has the ability to restart and relocate within the universe, in a whim. We currently have a lot of limited thoughts here on planet Earth, as the majority is entering a dangerous level of confusion & turmoil, when it comes to universal awareness.