A 2014 Ruling Fixed Dates That Used to Move Every Year

Until a formal ruling by the Universal House of Justice, the Baha'i Faith's supreme governing institution, took effect starting in 2015, the Twin Birthdays were set by a specifically lunar calculation tied to the Islamic calendar, causing the pair of holy days to shift by roughly eleven days earlier against the Gregorian calendar each year in the way lunar Islamic dates generally do; the 2014 ruling fixed the Twin Birthdays instead to specific, non-moving positions within the Baha'i Badi calendar itself, stabilising their placement relative to the Baha'i year and ending the year-on-year lunar drift that had applied under the older reckoning.

The change was part of a broader administrative clarification of the Badi calendar's practical application that the Universal House of Justice undertook in the early twenty-first century, addressing a number of open questions about how the calendar the Bab had originally established should actually be applied in Baha'i communities worldwide, and it illustrates a distinctive feature of Baha'i religious governance generally, that a single living administrative institution can issue a binding ruling settling a calendar question directly, a form of centralised doctrinal and practical authority that few of the other traditions covered in this atlas possess in comparable form.