Benedict's decision to live at the Vatican in retirement, be called "emeritus pope" and "Your Holiness" and to wear the white cassock associated with the papacy has deepened concerns about the shadow he might cast over the next papacy.
But Benedict has tried to address those worries over the past two weeks, saying that once retired he would be "hidden from the world" and living a life of prayer.
In his final speech in St. Peter's Square on Wednesday, he said he wasn't returning to private life exactly, but rather to a new form of service to the church through prayer.
Shortly before 5 p.m. Thursday, Benedict will leave the palace for the last time as pontiff, head to the helipad at the top of the hill in the Vatican gardens and fly to the papal retreat at Castel Gandolfo south of Rome.
There, at 8 p.m. sharp, Benedict will become the first pontiff in 600 years to resign. The doors of the palazzo will shut and the Swiss Guards will go off duty, their service protecting the head of the Catholic Church over — for now.
And on Monday, the cardinals are expected to begin meeting to set the date for the conclave.
Benedict's decision has been met for the most part with praise and understanding. Cardinals, Vatican officials and ordinary Catholics have rallied around him in acknowledgment of his frail state and the church's need for a strong leader.
But Sydney Cardinal George Pell has caused a stir by openly saying the resignation has been "slightly destabilizing" for the church.
In an interview with Australia's ABC radio, Pell noted that Benedict himself had acknowledged the shift in tradition; Benedict said Wednesday that he appreciated his decision was not only serious but "a novelty" for the church.