On his last day as pope, Benedict made a pledge of "unconditional obedience" and respect to whoever takes up the reins.
His promise came in a final meeting with the cardinals who will pick his successor, almost certainly from within their own ranks.
More than half the 115 cardinal-electors expected to take part in the conclave were appointed by Benedict, suggesting his influence will live on.
However, the Vatican has said that he won't interfere in the new pope's running of the church.
The situation of having a living pontiff in retirement is almost unprecedented for the church.
Video footage released by the Vatican on Friday showed the doors to the papal apartment there being ceremonially sealed by senior officials. They will remain closed until a new pope enters.
The Vatican has said it wants to have the next pontiff in place for the week of services leading up to Easter Sunday on March 31.
CNN iReporter Rummel Pinera, a blogger and campaigner from the Philippines, said Benedict's departure raises interesting questions for the Catholic Church -- such as whether to accept women priests, or a pope from Africa or Latin America, and whether to approve stem cell research.
"I'm hoping that Benedict XVI's successor will be open to progressive ideas, so that the Roman Catholic Church would be seen as a dynamic institution that can adopt to modern day situations," he said.