ROME — Pope John Paul I’s time as pope, although brief, remains an important example of the beauty and simplicity of faith, Pope Francis said.

In a preface to a new collection of his predecessor’s teachings and writings, Pope Francis wrote that God, through the late pontiff’s short pontificate, “found a way to show us that the only treasure is faith, the simple faith of the apostles.”

“It was precisely because of the faith of the Christian people to which he belonged that he was able to cast a prophetic gaze on the wounds and evils of the world, showing how much peace is also dear to the heart of the church,” he said.

The preface was published by the Vatican newspaper, L’Osservatore Romano, May 9.

The pope said that during his pontificate, Pope John Paul “confessed faith, hope and charity as God-given virtues” and insisted that care for the poor and needy was “an infallible part of the apostolic faith.”

Recalling the late pope’s prayers when he formally took possession of the Basilica of St. John Lateran in 1978, Pope Francis noted that his predecessor “cited the formulas and prayers he had learned as a child to reaffirm that the oppression of the poor and the ‘defrauding of the workers of their just wages’ are sins that ‘cry out for vengeance in the sight of God.'”

His public speeches calling for world peace, the pope said, were evidence of his hope that the church would “contribute to creating a climate of justice, brotherhood, solidarity and hope, without which the world cannot live.”

Pope John Paul, he wrote, showed that peace “was not the product of his own thinking” but of the Christian faith.

It is the same “faith he received as a gift in his family of workers and immigrants, who knew the toil of life to bring bread home; of people who walked on the earth and not in the clouds,” he said.

Quoting St. Oscar Romero’s 1978 homily after the late pope’s death, Pope Francis said that “with the death of two popes and two papal elections” that year, the world saw that the hierarchy of the Catholic Church is placed “‘on the shoulders of frail men,’ yet called to be ‘the channel through which the church is guided and governed’ and a ‘sacramental sign’ of the ‘grace that is given to men.'”

Through Pope John Paul’s death, “it was easy to recognize that the church is not built by the pope nor by the bishops: the successor of Peter is ‘the stone of consistency’ on which rests the unity of the church that Christ himself built, with the gift of his grace,” the pope wrote.

Pope Francis is scheduled to beatify Pope John Paul Sept. 4 at the Vatican.