The Source of Traditions on Imam al-Riḍā (Vol 2) · Hadith 348 (#Ḥadīth #348)

348 - وَبِهذَا الإسناد قالَ: قالَ رَسُولَ اللَّهِ صَلَّى اللهُ عَلَيْهِ وَآلِهِ: لا تفرد وَالجُمْعَةِ بصوم.

31-348 According to the same documentation, God’s Prophet (S) said, “Do not establish Friday as the only day of the week to fast.”

Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).