Warsaw, Jan. 21--(AP) A compilation of private letters by Pope John Paul II gives an unusual insight into his life, mixing personal touches with reflections on the state of the church while chronicling five decades of friendship with a Roman Catholic philosopher in his native Poland. Published in a small print run only in Polish, the book marks the first time the pope has opened his private correspondence to the public.

"Pelny Wymiar,'' or "Full Dimension,'' documents 161 letters between the pope and Stefan Swiezawski, a church historian and philosopher. The book starts in 1953 with a request from Rev. Karol Wojtyla - the future pope - for Swiezawski to review a post-doctorate thesis on Christian ethics and ends with a letter from the pope dated Sept. 19, 2001. "It is a monument to an extraordinary friendship that has continued for half a century, despite changing circumstances,'' the Rev. Robert Biel, whose Biblos publishing house printed 2,000 copies of the collection in October with Vatican authorization, said Monday.

In 1955, Wojtyla declines an invitation to join the Swiezawski family in Poland's mountains, saying he "can hardly move'' after a kayaking excursion. Later, he recalls visits by the family to the papal residence at Castel Gandolfo near Rome.

The pope's letters are brief and matter-of-fact but show him keeping abreast of developments in Poland after he became pontiff in 1978. In October 1989, Swiezawski wrote of his concerns about "chauvinism, a triumphant nationalist attitude coupled with anti-Semitism'' among the Polish clergy after the fall of communism that year. "I share your concerns and also your fears,'' John Paul responded. "What remains is prayer and a continuous effort.''

In a letter dated October 1978, he thanked Swiezawski for his congratulations on becoming pope and looked forward to the task ahead. "I am facing a test much more important than all previous ones but I fully entrust myself to Christ and I totally trust His Mother,'' he wrote, adding that he remembered Swiezawski predicting four years earlier he would become pope.

Biel said Biblos approached the Vatican for permission to print the letters after Swiezawski proposed their publication. "In recognition of their contribution to Catholicism and the church in Poland in the 20th century, they can be printed,'' replied the pope's secretary, Bishop Stanislaw Dziwisz.

John Paul's letters are set to be followed into Polish bookstores by his first poetic work since he became pope. The Vatican said last month that "The Roman Triptych'' would be published in the southern Polish city of Krakow, where Wojtyla spent four decades as a student, priest, bishop and cardinal before becoming pope. No publication date has been set.