Nassoshin Shari'a (rubutu) an saukar da su kuma sun zo mana cikin harshen Larabci, kuma ba zai yiwu a fitar da Ahkaam Shari'iyyah sai ta hanyarsa ba. Saboda haka, yana da muhimmanci ga Mujtahid ya san fannonin ilimin da suka shafi harshen Larabci; ka'idojinsa (Qawaa'id) da fiqhinsa (ka'idoji da fahimta). Wannan domin ya saba da abin da ya zama dole a gare shi daga fannonin ilimin harshe da za su ba shi damar yin Ijtihaad, fitar da hukunce-hukunce da fahimtar nassoshi.

The Shar’iyah Nusoos (texts) were revealed and came to us in the Arabic language and it is not possible to deduce the Ahkaam Ash-Shar’iyah except by it. For that reason, it is essential for the Mujtahid to be aware of the areas of study related to the Arabic language; its principles (Qawaa’id) and its Fiqh (rules and understanding). That is so that he can be familiar with what he necessarily requires of the linguistic areas of knowledge that will enable him to perform Ijtihaad, make deductions and understand the texts.

Malamai na Usulul Fiqhu sun saka cikin littattafansu wani bayani game da wasu al'amuran da suka shafi harshen Larabci wadanda suke da muhimmanci ga wanda ke karatun Usulul Fiqhu. Hakan ya kasance ne domin a fahimci wasu daga cikin kalmomin ilimin harshe da ake yawan ambata a cikin ka'idojin Usulul Fiqhu, kamar misali: Al-Haqeeqah da Al-Majaaz, Al-Haqeeqah Al-'Urfiyyah da Al-Haqeeqah Ash-Shar'iyyah, da Al-Ishtiraak da At-Taraaduf, tare da sauran ka'idojin harshe da ma'anoni.