Pope Francis railed against unjust employers Friday, saying it is hypocritical to go to church on Sunday and then exploit one’s workers.

“Many Christians, even Catholics, who say they are practicing Catholics exploit people! They exploit their workers!” the pope said during his daily homily at Mass in the Casa Santa Marta Friday.

They send them home at the beginning of summer to avoid having to pay benefits and then take them back again at the end, he explained.

“And so many of these call themselves Catholics. They go to Mass on Sundays and then they do this. This is a mortal sin!” he said.

“How many humiliate their workers!” he added.

This is not the first time that Francis has used strong language to condemn the exploitation of employees.

Last May, the pope preached a similar homily, saying that those who exploit people at work, pay their employees under the table, do not contribute to their pension, and “scams” on their wages should not even call themselves Christians.

“It is sin,” a “mortal” sin, he said.

“Woe to you who exploit others and their work by evading taxes, not contributing to their pension funds, and not giving them paid vacation. Woe to you!” he said.

“This injustice is a mortal sin,” he said.

“’Woe to you who are rich.’ If one were to preach like this today, the headlines in the next day newspapers, would say: ‘That priest is a Communist!’” he said. “But poverty is at the center of the Gospel. Preaching about poverty is at the center of Jesus’ message: ‘Blessed are the poor’ is the first of the Beatitudes.”

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