Kitob va Sunnatdan hukm chiqarish arab tilini bilishga va uning turlarini bilishga bog'liqdir, chunki ular arab tilida nozil qilingan. Alloh taolo aytadi: "Arab tilidagi ravshan til bilan" (Shuaro surasi, 195-oyat). Shuning uchun tilning va uning turlarining masalalarini zikr qilish zarurdir. Tilning turlaridan usul al-fiqhda faqat hukmni istinbot qilish bilan bog'liq bo'lganlarini bayon qilish kifoya, chunki usul al-fiqhda bundan boshqasini muhokama qilish kerak emas. Bundan tashqari, Kitob ham, Sunnat ham xabar (xabar berish) va inshoʼ (talab va ifoda) turlariga bo'linadi. Ammo usul olimi faqat inshoʼni o'rganadi, xabarni emas, chunki ko'pincha hukmlar xabarda emas, balki inshoʼda belgilanadi. Shu sababli Kitob va Sunnatdagi gap quyidagicha bo'linadi: buyruq (amr) va taqiq (nahiy), umumiy ('aamm) va xos (xaass), mutlaq (mutlaq) va muqayyad (cheklangan), mujmal (qisqa va umumiy bayon) va mubayyan (batafsil bayon), nosix (bekor qiluvchi) va mansux (bekor qilingan). Shunga ko'ra, tildagi bu masalalarni va Kitob hamda Sunnatning mazkur turlarini jamlab muhokama qilish zarur bo'ladi, toki shariat hukmlarini Kitob va Sunnatdan istinbot qilish mumkin bo'lsin.

The inference from the Kitaab and the Sunnah depends on knowing the language of the Arabs, and knowing its divisions, because they are sent down in the language of the Arabs. Allah Ta'ala said: In an Arabic clarifier tongue) 195 Surat Al-Shu'araa', therefore it is inevitable to mention the discussions of the language and its divisions. And what would be discussed from the divisions of the saying is that which is related to the derivation of the verdict only, since there is no need to discuss other than that in usoul al fiqh. Further more both the Kitaab and the Sunnah are divided into tiding (khabar/news) and composition (inshaa'), however the scholar of the usoul ponders to the inshaa' only without the khabar because in most cases the verdicts are not established in it, from here the saying in the Kitaab and Sunnah is divided into: command (amr) and prohibition (nahi), general ('aamm) and special (khaass), unrestricted (mutlaq) and limited (muqayad), summed up (mujmal) and detailed (mubayan), abrogator (naasikh) and abrogated (mansoukh). Accordingly it is inevitable to summing up a discussion in the language, and in these divisions of the Kitaab and the Sunnah, to be able to infer from the Kitaab and the Sunnah over the shari'ahi verdicts.