Why don’t Christians celebrate Easter on the same date?

Easter is the central celebration of Christianity, but, paradoxically, not all Christian confessions commemorate it the same day. The difference in dates is mainly due to astronomical and calendar issues that have evolved throughout history.

According to the prioress of the monastery of the conversion of the Agustinas sisters of Madrid, Carolina Blázquez, “the Christian Easter is celebrated in relation to Jewish Easter”, since the passion, death and resurrection of Jesus occurred historically on that holiday. Jewish Easter takes place on Nisan 14, one month from the Hebrew calendar that follows a lunar cycle and whose date varies between March and April.

To calculate the date of the Christian Easter, the first Christians tried to determine the spring equinox, establishing as a reference on March 21. However, “this does not always correspond to astronomical reality, since it varies a few days,” explains Blázquez. This uncertainty led to the traditionally existed two criteria to set the date of Easter, which generated discrepancies between the different Christian traditions.

The Cisma of the Calendar

The council of Nicea, held in the year 325, tried to unify with a single criteria the calculation of the Pascual date, establishing on Sunday after the first full moon after the spring equinox.

That first ecumenical council, that is to say the first meeting of Christian bishops held in Nicea (today İznik, in Turkey), also placed the foundations to reach a consensus in the Church through an assembly that would represent all Christianity. In addition “a common agreement was reached and for 1,300 years Easter was held jointly.”

However, in the 16th century, the reform of the calendar introduced by Pope Gregory XIII marked a new division between the Christian churches.

“Before the Julian calendar was followed, imposed by the Roman Empire but, over the years, due to inaccuracies in astronomical measurement, a 10 -day gap with respect to the real cycles of the Moon had accumulated,” explains the associate professor of the Spanish University of San Dámaso.

To correct this problem, the Gregorian calendar adjusted the measurement of time, eliminating the lag that had accumulated until that moment.

However, the Orthodox churches, although over time they adopted the Gregorian calendar for day -to -day civil and organizational issues, “continue to use the Julian calendar to set the liturgical dates,” explains Blázquez. “Therefore, there is a gap that is currently about 13 days between both traditions,” says the expert.

For this reason, Catholics and Protestants celebrate Easter according to the Gregorian calendar, while the Orthodox do so following the Julian.

An obstacle to Christian unity

The division on the date of Easter is seen by many as an ecumenical problem. Pope Francis has repeatedly expressed the need to unify it. In a public statement in Lartán’s basilica, he came to say that, if the orthodox criterion is followed without adjustments, “there will be a time when we will celebrate Easter in August.”

The specialists have responded that this will not happen within about 400 years, but the statement of Pope Francis highlights the growing lag for orthodox, which the Julian calendar continues to be used for liturgical issues.

In the ecumenical field, several proposals have been born to settle this issue. “Orthodox propose to rely exclusively on astronomical data, without following the Julian or Gregorian calendar,” explains Blázquez. This would imply calculating the spring equinox every year based on the Jerusalem meridian, since “Jesus died in Jerusalem and that would be a unifying criterion.”

However, the current proposal launched on an unofficial way by Pope Francis suggests setting a stable date for Easter, for example, on the second Sunday of April. In this sense, Blázquez warns that “for orthodox, the link with astronomical cycles is very important, since the Easter liturgy is closely related to the full moon and the symbolism of light overcoming darkness.”

A future with a common Easter?

Beyond the astronomical and calendar issues, unifying the Easter date would mean a breakthrough on the way to the unity of Christians. Blázquez points out that “when the change was made to the Gregorian calendar in the 16th century, there was already the division between the East and West, so the Orthodox did not participate in the decision.”

Today, however, a common agreement would be a sign of reconciliation. “Pope Francis insists right that celebrating Easter on different dates is an antitestimony,” explains Blázquez.

And he adds: “What great testimony would it be that, when each Christian in the world is in their parish, in their monastery or at home celebrating the resurrection, know that all Christians in the world are doing it at the same time.”