在摩塔拉事件(Mortara affair)上,他請求教皇歸還由女僕施行浸禮、被宗教裁判所扣留的猶太小孩Edgardo Mortara,遭到拒絕。
He had less luck with the Pope, who refused to return Edgardo Mortara, a Jewish child who had been baptised by his housemaid and kidnapped from his family by the Inquisition.