This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The systems traditions use to divide their scriptures were mostly settled centuries after the texts themselves. The weekly Torah portion cycle used in synagogues today traces to ancient reading practice but was standardized only gradually; the chapter numbers now printed in every Bible were added in the thirteenth century, commonly credited to Stephen Langton, and the verse numbers familiar today came later still, added to a printed New Testament in the sixteenth century. Neither system existed when the underlying texts were composed, and both were added specifically to make citation and comparison possible.
Other traditions solved the same problem their own way and on their own timeline. The Quran was divided into surahs of clearly unequal length from very early in its transmission, ordered roughly by length rather than by chronology of revelation, while Buddhist scripture is grouped into nikayas, collections sorted by the length or form of the discourse rather than by subject. Comparing how differently each tradition chose to cut up its own text is itself a small window into what each tradition thought was worth keeping together.
None of these systems is native to the text it now organizes; every one of them was layered on afterward by later readers trying to make a long, originally undivided work easier to study, teach and cite accurately, which is worth remembering whenever a chapter or verse boundary is treated as though the original author had placed it there.