Hakeemul Ummah Hazrat Moulana Ashraf Ali Thaanwi Sahib رحمه الله has said that sins erase علم (knowledge). The mere knowledge of words (textual knowledge) coexists with sin and even with kufr. Thus, there are experts of the language in Beirut and Germany (in the west in general). The reality of علم (knowledge) is a Noor regarding which the Holy Qur’ān says; “Verily there has come to you a Noor from Allah and a clear Kitaab.” علم (knowledge) is also described as Rooh. The Holy Qur’ān says; “We aided them with a Rooh.”
(SOURCE: MALFOOZAAT OF HAZRAT MOULANA ASHRAF ALI THAANWI SAHIB رحمه الله, PART 6)