Al-Sakkākī’s treatment makes the agreement at the ending central to recognizing sajʿ, even though different formulations may describe correspondence of fawāṣil more generally. The end of each prose unit is evaluated for its audible relation to the next.
The term sajʿ can denote the device, while fāṣilah denotes the closing word in which correspondence is heard. Practical analysis therefore identifies the clauses and the relevant closing expressions.
A semantic comparison or equality of pattern alone is not sufficient for sajʿ when the requisite ending correspondence is absent.