Determining a precise "start date" for Easter as a holiday is tricky because its development was a gradual process rooted in both Jewish tradition and early Christian practices. Here's a breakdown of the key periods:
* Early Christianity (1st-2nd Centuries CE): Early Christians, many of whom were Jewish, observed a commemoration of the Passion of Christ, his crucifixion, burial, and resurrection. This observance was initially linked to the Jewish Passover (Pesach), likely seen as fulfilling prophecies about the Messiah. There wasn't yet a unified, universal celebration across all Christian communities. Different dates were used based on local traditions and calendrical calculations.
* The Quartodeciman Controversy (2nd Century CE): This was a major dispute about when to celebrate Easter. Some Christians, primarily in Asia Minor (the "Quartodecimans," meaning "fourteeners"), celebrated it on the 14th day of Nisan, the date of Passover, regardless of the day of the week. Others, particularly in Rome and Alexandria, celebrated it on the Sunday following the 14th of Nisan. This disagreement highlighted the lack of a single, authoritative practice.
* The Council of Nicaea (325 CE): This ecumenical council, convened by Emperor Constantine, addressed many issues facing the early Church, including the Easter controversy. The Council decreed that Easter should be celebrated on the Sunday after the first full moon following the spring equinox. This was an effort to standardize the date and separate it definitively from the Jewish Passover. However, disagreements and variations in calculation persisted for centuries.
* Later Developments (Post-Nicaea): Even after Nicaea, different methods of calculating the date (primarily due to differing calendars: Julian vs. Gregorian) led to Easter being celebrated on different dates in the Eastern and Western churches. The Gregorian calendar reform in 1582, adopted by the Catholic Church and later by most Protestant countries, further widened the gap with Eastern Orthodox churches, which continue to use the Julian calendar for calculating Easter.
In summary:
* There wasn't a single moment when Easter "became" a holiday.
* Its origins lie in the earliest days of Christianity.
* The Council of Nicaea in 325 CE was a crucial step in standardizing the date.
* Easter developed over time through evolving practices and theological interpretations.
While it's impossible to point to a single date, the 4th century, following the Council of Nicaea, marks a significant turning point in the establishment of Easter as a more universally recognized and defined Christian celebration.