VATICAN CITY – Hours before opening the Synod of Bishops, Pope Francis prayed the bishops would express themselves and listen to each other openly, trusting in God to reconcile their differences.

"Let us invoke openness to a sincere, open and fraternal exchange of views, that it might lead us to take pastoral responsibility for the questions that this changing time brings with it," the pope said.

"Let them fill our heart, without ever losing peace, but with serene trust that in his time the Lord will not fail to lead us back to unity."

Pope Francis spoke in St. Peter's Square during an Oct. 4 prayer vigil for the Oct. 5-19 synod, which is discussing a range of "pastoral challenges of the family."

In his talk, the pope spoke generally about the need for pastoral solutions suited to the present day.

"We must lend an ear to the rhythm of our time and perceive the odour of people today, that we might be imbued with their joys and hopes, their sadness and anxiety: at that point we will be able credibly to propose the good news on the family," he said.

Pope Francis has made a point of recognizing realities that conflict with Catholic teaching on the family, baptizing a child whose parents had been married civilly and marrying couples who had cohabitated before their wedding.

The pope emerged from the basilica shortly after 7 p.m.

Many in the congregation held candles as they listened to him contrast the pleasures of the family hearth with the suffering of the lonely in the "bitter twilight of broken dreams and projects."

The pope called such people victims of an "individualistic culture that denatures and renders ephemeral the ties" among human beings.

"The family continues to be the unparalleled school of humanity, an indispensable contribution to a society of justice and solidarity," he said.