«لا يتغير به حكم من أحكام النص»
A ruling established by a text must not be changed through analogy.
The book discusses imposing an intention requirement on ablution by comparison with tayammum, if the result would restrict what its Hanafi reading treats as an unrestricted textual rule. This is a Hanafi usuli illustration; juristic schools differ over intention in ablution.
The first condition excludes a direct clash with text. The second excludes changing the scope or conditions of a text through an analogy that appears merely to add a qualification.