By David Willey
BBC News, Rome
The commemoration at St Peters was led by Pope Benedict XVI
Pope Benedict XVI has commemorated the third anniversary of the death of his predecessor, Pope John Paul II.
Thousands of pilgrims crammed into St Peter's Square, in the Vatican, for the solemn commemoration of the 84-year-old's death.
More than 30 cardinals attended the open air mass.
Among them was Cardinal Stanislaw Dziwisz, the former pope's private secretary, now Archbishop of Krakow, John Paul's home town in Poland.
Pope Benedict recalled the millions of pilgrims who flooded into Rome from Poland, and many other countries, to pay their last respects to almost the longest reigning pope in history, now on the fast track to sainthood.
Pope Benedict praised the outstanding qualities of his predecessor.
"He had exception spiritual and mystical qualities. You only had to watch him when he prayed," Pope Benedict said.
This week, Vatican officials announced they have completed their inquiries into the saintly life of Pope John Paul.
It is widely expected that the late pope - who is already venerated by an unending stream of pilgrims who come to visit his tomb - will, within a year or two, be declared by the Catholic Church a blessed, the final step on the road to formal sainthood.