“Once Rasulullah (sw) entered the Mosque and found a group of people gathered around a man. He asked, 'Who is he?'. It was said that he was a Allamah. He then asked them, 'What is that?'. They replied that he is the most learned man about the genealogy, the chronology, and the history of the pre-Islamic days of darkness and the poetry of Arabs. He (a.s) said, so the Prophet (sw) then stated that ‘such knowledge doesn't harm the one who is ignorant of it or benefit the one who knows it.' Then he (sw) added: ‘Knowledge consists of three kinds: A clear verse (of the Qur'an), a just obligation (i.e. a legal ruling) or an established sunnah (i.e. a hadith). Anything else is of the extra achievements.”’