Hey, well, now that was surprising. Not every day do you read the Pope is retiring. Wow. I wonder how this jibes with that Malachian prediction that this is the last pope before the end of the world. Seems we may not have much time left.
I can see the Holy Father retiring in part because he has the freedom that Christians ought feel, that freedom not to follow conventions but to possess a spirit of liberty. Thus the fact no pope has retired since 1415 wouldn't be much of a deterrent to this holy pope. And he might well have considered that his predecessor, Pope John Paul II, already taught by his example of the dignity of old age and that the value of human life is apart from what can be “produced”.
Finally, the timing seems interesting given that this comes on the heels of producing the three volume work on the life of Christ. At the beginning of his papacy he wondered if he'd complete it before his death, and perhaps once it was done he felt he'd accomplished what he'd set out to do.
Of course another reason for his leaving, besides simply that it's his discernment of God's will, is that he can't travel anymore and in this day and age travel seems almost a job requirement for that position.