In his final general audience Pope Benedict XVI this morning admitted that his pontificate had difficult moments when "the Lord seemed to sleep" but expressed the assurance that despite "rough seas" God would not let the barque of Peter sink.

Speaking to hundreds of thousands of well-wishers packed into a sunny St Peter's Square, the Pope gave a highly personal message in Italian, and said that he had made the decision to step down, after much prayer, "in full awareness of its severity and also its novelty, but with a deep peace of mind". He said he had acted for the good of the Church.

In words that will serve as a warning to cardinals who might wish to succeed him on the throne of St Peter, Benedict XVI said that a pope "no longer has any privacy ... He belongs always and totally to everyone, to the whole Church. His life is, so to speak, totally deprived of the private sphere."

He also said that after his resignation comes into effect tomorrow he would not "abandon the Cross, but [would] remain in a new way near to the Crucified Lord".

He said he would remain "in the service of prayer" rather than return to private life "of travel, meetings, receptions, conferences and so on".

He talked about his reaction to being elected Pope almost eight years ago. "In that moment, as I have already stated several times, the words that resounded in my heart were: "Lord, what do you ask of me? It is a great weight that you place on my shoulders, but, if you ask me, at your word I will throw out the nets, sure that you will guide me".

But he added: "The Lord really has guided me. He has been close to me: daily could I feel His presence."

Likening the Church's journey to the apostles' boat caught in a storm on the Sea of Galilee, he said the last eight years had "seen moments of joy and light, but also difficult moments".

"The Lord has given us many days of sunshine and gentle breeze, days in which the catch has been abundant; [then] there have been times when the seas were rough and the wind against us, as in the whole history of the Church it has ever been - and the Lord seemed to sleep.

"Nevertheless, I always knew that the Lord is in the barque, that the barque of the Church is not mine, not ours, but his - and he shall not let her sink. It is he who steers her: to be sure, he does so also through men of his choosing, for he desired that it be so."

"This was and is a certainty that nothing can tarnish. It is for this reason, that today my heart is filled with gratitude to God, for never did he leave me or the Church without his consolation, his light, his love."

The Pope explained that he had called for the current Year of Faith to strengthen people's faith at a time when it is being pushed "more and more toward the margins of life".

In a simple, direct statement of his own faith and hope, he said: "I would like everyone to feel loved by the God who gave His Son for us and showed us His boundless love. I want everyone to feel the joy of being Christian."

The Pope then thanked the Roman Curia and the cardinals for their support, along with the diocese of Rome. He also paid tribute to diplomats accredited to the Holy See.

Sounding a pastoral note he thanked people "throughout the whole world, who, in recent weeks have sent me moving tokens of concern, friendship and prayer". He added: "Yes, the Pope is never alone: now I experience this [truth] again in a way so great as to touch my very heart."

He said he was especially touched by letters he received from ordinary people. "These people do not write to me as one might write, for example, to a prince or a great figure one does not know. They write as brothers and sisters, sons and daughters, with the sense of very affectionate family ties."

"To experience the Church in this way and almost be able to touch with one's hands the power of His truth and His love, is a source of joy, in a time in which many speak of its decline," he said.

After he finished speaking he greeted pilgrims in St Peter's Square in various languages. In English he said the decision he made to resign, "after much prayer, is the fruit of a serene trust in God's will and a deep love of Christ's Church".