The following is a list of gradings for the letters in Nahjul Balagha. The methodology that was used in this grading of the letters is by listing the sources that predate Nahjul Balagha, or those that were compiled after Nahjul Balagha as long as the late source provides a chain that predates Al-Shareef Al-Radhi. Those sources were then studied to ascertain if there existed a disconnection in the chain or included unreliable narrators.
It goes without saying that the gradings for these sources are based on Shia standards, and therefore, only strictly Shia compilations will be graded, since other sources are unreliable according to Shias by default.
The sources that we have returned to are based on the work of Abdul Zahra’ Al-Hussaini, who spent fifteen years gathering his material in his Masadir Nahjul Balagha.
Note: Letters #24, #25, #47, and #68 and authentic according to Shia hadith standards.