From Light of The World – An interview with Peter Seewald:
The great majority of these cases took place decades ago. Nevertheless they burden your pontificate now in particular. Have you thought of resigning?
“When the danger is great one must not run away. For that reason, now is certainly not the time to resign. Precisely at a time like this one must stand fast and endure the difficult situation. That is my view. One can resign at a peaceful moment or when one simply cannot go on. But one must not run away from danger and say that someone else should do it.”
Is it possible then to imagine a situation in which you would consider a resignation by the Pope appropriate?
“Yes. If a Pope clearly realizes that he is no longer physically, psychologically, and spiritually capable of handling the duties of his office, then he has a right and, under some circumstances, also an obligation to resign.”