The calendar of Biblical feasts

In ancient Israel, Essenes were a group living in secluded communities. Historical accounts from the first century, provided by Josephus Flavius and Philo of Alexandria, offer descriptions of their distinct practices. The Essenes notably diverged from other Jewish traditions, particularly in their observance of feasts, using their own calendar system.

The discovery of the Qumran scrolls revealed the existence of two Jewish calendars for festivals, providing new insights into the events of the Passion Week. It is now generally accepted that during the time of the Gospel, two calendars were used in Israel.

One of the calendars in ancient Israel was based on the lunar cycle and was utilized in the Temple of Jerusalem. Each month began anew when two witnesses observed the new moon and confirmed it before the Sanhedrin. This calendar determined the specific days for feasts and holidays and became central to Jewish religious life. Even today, the Jewish calendar retains this lunar basis, though now it is pre-calculated without requiring witnesses. Using this system, festivals like Passover and the Feast of Tabernacles align with specific lunar phases, particularly the full moon. The months' names, such as Nissan, Tishri, Teveth, and Adar, were adopted from Babylon.

The Essenes, however, separated themselves from this lunar system, which led to divisions among Jewish religious groups. While the Sadducees and Pharisees followed the lunar calendar, the Essenes adhered to a solar calendar, which they considered a pure, ancient tradition. This calendar consisted of 364 days, structured into 52 weeks.

According to this calendar, the first month of the year, Nisan, always began on a Wednesday. The fifteenth day of Nisan, also a Wednesday, marked the start of Passover. Wednesday, the fourth day of creation, is described in Genesis 1:14 as the day when God created the sun and the moon to signify the seasons. The Feast of Tabernacles, too, began on a Wednesday in this calendar. Sunday, being the first day of creation, commemorated the moment when the Almighty created light. The Essenes, who referred to themselves as "Sons of Light," celebrated the Festival of Waving the Sheaf seven days after the Feast of Unleavened Bread. Following this, they began the Counting of the Omer, which culminated fifty days later in the Feast of Weeks, known as Pentecost. Another fifty days later, they celebrated the Feast of Wine, and fifty days after that, the Feast of Oil. All these celebrations fell on the first day of the week — Sunday.

In the Gospels, there are several accounts of Jesus and his disciples celebrating Passover. According to the Synoptic Gospels (Mark, Matthew, and Luke), they celebrated Passover the night before Jesus' arrest. However, John's Gospel narrates that the Last Supper occurred the night before the start of Passover. John notes that the priests who brought Jesus to the Praetorium did not enter its courts to avoid defilement, as they needed to eat the Passover lamb that evening, Friday night, according to the Temple calendar (John 18:28): "But they themselves did not go into the Praetorium, lest they should be defiled, but that they might eat the Passover."

It is widely accepted that Jesus was crucified in 30 AD. Calculations indicate that, in that year, Passover according to the solar calendar fell on Wednesday, while the lunar calendar placed it on Saturday, which began on Friday evening.

Christian tradition identifies the Western Hill of ancient Jerusalem, known among Christians as Mount Zion, as the location of the Last Supper of Jesus with his disciples. (See also article "Last Supper Room")

Archaeological excavations of the 20th century, including the discovery of the Essene Gate mentioned by Josephus Flavius (Flavius J., The Jewish War, 4.120), as well as the ruins of massive structures with ritual baths designed for the purification of large groups, suggest that this area was home to an Essene quarter.

It is noteworthy that the Book of Acts (6:7) states,

"Then the word of God spread, and the number of the disciples multiplied greatly in Jerusalem, and a great many of the priests were obedient to the faith."

However, the author does not identify them as Sadducees. Could it be that these were the dissident priests from among the Essenes? (See also article "The worldviews of Qumran's community")