Pope Francis has offered his condolences and prayers for the victims of Saturday’s synagogue shooting in Pittsburgh and their families, calling the attack an “inhuman act of violence.”

“I express my closeness to the city of Pittsburgh, in the United States of America, and in particular to the Jewish community, struck yesterday by a terrible attack in the synagogue,” the pope said Sunday before a crowd of some 25,000 pilgrims in Saint Peter’s Square in the Vatican.

“May the Most High welcome the deceased into his peace, comfort their families and sustain the wounded,” he said.

“We are all, in fact, wounded by this inhuman act of violence,” Francis continued. “May the Lord help us to extinguish the eruptions of hatred that emerge in our societies, strengthening the sense of humanity, respect for life, moral and civic values, and the holy fear of God, who is Love and Father of all.”

The pope has repeatedly condemned anti-Semitism as a great moral evil of our times, insisting that all Christians “must be firm in deploring all forms of anti-Semitism, and in showing their solidarity with the Jewish people.”

Francis has appealed for a common Judeo-Christian witness “to the sanctity of God and human life.” God is holy, he said in April 2015 in a meeting with European rabbis, “and the life He has given is holy and inviolable.”

Not only those who perpetrate violence and spread hate are to blame for the evils of anti-Semitism, he said last January, but also those who allow it to fester through their indifference or apathy.

Speaking before participants in a conference on the responsibility of States, institutions and individuals in the struggle against anti-Semitism, the pope underscored the wider complicity of a society that sometimes turns a blind eye to the evils being carried out in its midst.

The enemy against which we fight “is not only hatred in all of its forms,” Francis said, “but even more fundamentally, indifference; for it is indifference that paralyzes and impedes us from doing what is right even when we know that it is right.”

Reflecting on the early pages of the biblical Book of Genesis, where God asks Cain: “Where is your brother?” Francis said that Cain’s attempt to shirk his responsibility — “Am I my brother’s keeper?” — reveals a deep spiritual sickness.

“His brother does not interest him: here is the root of perversity, the root of death that produces desperation and silence,” he said.

“I recall the roar of the deafening silence I sensed two years ago in Auschwitz-Birkenau: a disturbing silence that leaves space only for tears, for prayer and for the begging of forgiveness,” he said.

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