As for fasting on the fifteenth day by itself (1), there is no textual basis for it; indeed, singling it out is discouraged. The same applies to turning that day into a festive occasion on which special dishes are prepared and decorations displayed: this is one of the newly-invented seasons that have no foundation in the religion.
Likewise, the practice that has appeared on the night of mid-Shaʿbān—namely, the large public gathering for the so-called “thousand-unit prayer” (2) in the main congregational mosques, the neighborhood and alleyway mosques (3), and even the marketplaces—is objectionable. It is an assembly for a voluntary prayer tied to a specific time, a fixed number of units, and an amount of recitation for which no divine sanction exists, and so it is disliked. The ḥadīth cited regarding the “thousand-unit prayer” (4) is fabricated by unanimous agreement of the ḥadīth scholars; and when a report is of that nature, it is impermissible to deem a prayer recommended on its basis. If the act itself is not recommended, then any practice that implies its recommendation is likewise disliked.
Were it allowed to create a novel congregational prayer for every night that has some degree of merit, people would perform that very prayer—or something longer or shorter (6)—on the two nights of the ʿĪds and on the night of ʿArafah, just as certain regions already hold a similar gathering on the first night of Rajab (5).
I have also been informed (7) that in some villages they pray after Maghrib a congregational prayer identical to Maghrib, calling it “the prayer of filial devotion.” And some people used to perform