7. Ali ibn Ibrahim has narrated from his father from Ibn Abi ‘Umayr from ‘Abd al- Rahman ibn al-Hajjaj who has said the following: ‘‘Once I asked abu al-Hassan Musa عليه السلام ‘If I needed to visit a Christian physician, can I offer the greeting of peace and pray for him?’ The Imam said, ‘Yes, but your prayer will not benefit him.’”