It was narrated that Anas said: "The Messenger of Allah(saw) was in Baqi', and a man called out to another man: '0 Abul- Qasim!' The Messenger of Allah(saw) turned to him, and he said: 'I didn't mean you.' The Messenger of Allah(saw) said: 'Call yourselves by my name but do not call yourselves by my Kunyah.'''(Sahih)