The quote from Luke refers to the faith that the people had in Jesus that allowed them to be healed by him. Their faith allowed miracles to be worked on them, not because of them.

The quote from Mark is pretty ambiguous. Anyone who says that any geographical feature of Earth will change at some time in the future is correct. Maybe its a reference to the fact that everything changes and/or comes to an end. But at the same time I think there is more going on than just this.