The Catholic Church is like a window into which the light of truth shines and through which a response of love should radiate, the pope said in his homily. “The church herself is like a window, the place where God draws near to us, where he comes toward our world.”

He said the throne in Bernini’s sculpture symbolizes the authority Jesus gave to Peter, supported by four ancient church theologians — two doctors of the church from the East and two from the West, representing the unity and diversity within the universal church.

The support of the theologians “teaches us that love rests upon faith. Love collapses if man no longer trusts in God and disobeys him,” the pope said.

“Everything in the church rests upon faith: the sacraments, the liturgy, evangelization, charity,” as well as “the law and the church’s authority,” he said.

Catholics cannot make things up as they go along, he said. They must follow tradition, the Sacred Scriptures and the teaching of the apostles explained and interpreted by the fathers of the church and the popes.

“The church is not self-regulating, she does not determine her own structure, but receives it from the word of God, to which she listens in faith as she seeks to understand it and to live it,” he said.

All the church teaches and does in the world must be motivated by love and lead to love, the pope said.

“A selfish faith would be an unreal faith,” Pope Benedict said.