Jewish law's prohibition on destroying anything bearing the divine name gave every synagogue a practical problem: worn prayer books, damaged scrolls and outdated documents had to go somewhere, and a genizah, typically a storeroom or a walled off chamber, was the ordinary answer, with contents eventually removed for burial in a cemetery. Most genizot were used exactly this way and left little for later scholarship. The exception that transformed the practice's reputation entirely was the genizah of the Ben Ezra Synagogue in Fustat, old Cairo, which accumulated material for centuries longer than most communities preserved theirs and was never fully cleared.
The Cambridge scholar Solomon Schechter examined its contents in 1896 and 1897 and recognized that the storeroom held not only religious texts but personal letters, contracts, medical writings and marriage documents spanning centuries of Mediterranean Jewish life, material later brought largely to Cambridge and other collections. The Cairo Genizah remains the reason a ritual disposal practice, followed quietly by synagogues everywhere for centuries without any expectation of scholarly use, is now cited as one of the richest single archives for the social history of the medieval Jewish world.