Brother human beings, which goes without saying. When these words are publicly uttered by a pope, Catholics are led to believe that the "brotherhood" to which he refers must be of a spiritual nature. Churchmen such as Francis with track records of religious indifferentism falsely imply spiritual congruence between conflicting beliefs.
St John Damscene against the Muslims
Satan Must Reign in the Vatican. The Pope Will Be His Slave.
Francis is not the first post Vatican II pope to call Muslims our brothers.