Various explanations have been advanced for the reading of Ecclesiastes at the Feast of Tabernacles, a practice that does not seem to have begun before the Middle Ages, and that has never been applied with great consistency even amongst the Jewish communities that adopted it. Such a reading is not mentioned in the minor tractate Soferim (xiv.3), which does list the reading of the other four Scrolls, and which is commonly dated to the eighth century; by the beginning of the eleventh century, on the other hand, all five Scrolls have been grouped together in Codex Leningrad (and probably also in the Aleppo Codex), even though they are not yet arranged there in the order of the festivals with which each was associated. It seems probable that Ecclesiastes was the last book to be drawn into a process which incorporated the reading of complete texts at each festival, following the model set by the use of Esther at Purim and Lamentations on the Ninth of Av. Those two books, of course, relate directly to the events that are being commemorated; the others do not, and their selection may have been driven more by their relative brevity than by any other consideration: Ecclesiastes, the last selected, is longer than the other Megillot, but still shorter than the remaining Ketuvim. If such practical and liturgical considerations created this group of books, however, it seems likely that the existence of the group came to influence the way in which each was understood. Both Ecclesiastes and Song of Songs, in particular, found themselves associated with texts that had a narrative structure and/or a close relationship with the broader narrative of Jewish history. With the rise of printing, this aspect of their context was further emphasized by the common practice of presenting the texts of, or commentaries on the Five Scrolls and the Pentateuch together. The two least specifically Jewish books of the Hebrew Bible, both of which had excited earlier controversy about their status, came in this way to find themselves set firmly within Judaism’s account and commemoration of its past.
Weeks, S. (2016). Solomon and Qoheleth. In B. J. Embry, & A. Erickson (Eds.), Megilloth studies : the shape of contemporary scholarship (71-86). Sheffield Phoenix Press