It’s an artifact of combining the Jewish Lunar and Catholic Gregorian Solar Calendars. Passover always starts on the first full moon after the first new moon after the spring equinox. Easter is always celebrated on Sunday and because the Last Supper fell on a Thursday night (Friday for the Jews because they start the day at sunset) then Easter is always on the Sunday after Passover.
The Roman Catholic Church was upset some Christian churches still disregard the Council of Nicaea and dare to celebrate Easter on Nisan 15 AKA Passover, or on the Sunday following Passover. So, in 1997, the World Council of Churches, a front organization for bringing the Protestants back under Rome, gathered all of the Christian member denominations together and tried to hash out a common date, which would basically be the Roman Catholic date. Read 10. (e) below and you'll see the importance of the spring equinox to the Roman Catholic Church and their refusal to budge on that.
I won't quote the entire document but you can click on the link below to verify my summary of points 1-6.
Towards a Common Date for Easter
World Council of Churches / Middle East Council of Churches Consultation
Aleppo, Syria
March 5 - 10, 1997
Historical background to the present differences
The New Testament indicates that Christ's death and resurrection were historically associated with the Jewish passover, but the precise details of this association are not clear. According to the synoptic gospels, Jesus' last supper was a passover meal, which would place his death on the day after passover, while according to John his death occurred on the day itself, indeed at the very hour, when the paschal lambs were sacrificed. By the end of the 2nd century some churches celebrated Easter/Pascha on the day of the Jewish passover, regardless of the day of the week, while others celebrated it on the following Sunday. By the 4th century, the former practice had been abandoned practically universally, but differences still remained in the calculation of the date of Easter/Pascha. The ecumenical council held at Nicea in 325 AD determined that Easter/Pascha should be celebrated on the Sunday following the first vernal full moon. Originally passover was celebrated on the first full moon after the March equinox, but in the 3rd century the day of the feast came to be calculated by some Jewish communities without reference to the equinox, thus causing passover to be celebrated twice in some solar years. Nicea tried to avoid this by linking the principles for the dating of Easter/Pascha to the norms for the calculation of passover during Jesus' lifetime.
While certain differences in the mechanics of determining the date of Easter/Pascha remained even after Nicea, which occasionally resulted in local differences, by the 6th century the mode of calculation based on the studies of Alexandrian astronomers and scholars had gained universal acceptance. By the 16th century, however, the discrepancy between this mode of calculation and the observed astronomical data was becoming evident. This led to the calendar change introduced by Pope Gregory XIII in 1582. Since that time, western Christians have come to calculate the date of Easter on the basis of this newer Gregorian calendar, while the eastern churches generally have continued to follow the older Julian calendar. While calendrical changes in some of the Orthodox churches in 1923 affected fixed-date feasts, the calculation of the Easter date remained linked to the Julian Calendar. Our present differences in calculation of the date of Easter thus may be ascribed to differences in the calendars and lunar tables employed rather than to differences in fundamental theological outlook.
In its study of the mechanics of the paschal calculation, the consultation took note of the fact that both the current eastern (Julian) and the current western (Gregorian) calculations diverge in certain respects from the astronomical data as determined by precise scientific calculation. As is well known, the Julian calendar at present diverges from the astronomical by thirteen days; the Gregorian at present does not diverge significantly, though it will in the distant future. Less well known is the fact that both Julian and Gregorian calculations rely upon conventional tables for determining the lunar cycle. For both modes of calculation, these tables at times give results that diverge from the astronomical data.
The continuing relevance of the Council of Nicea
In the course of their deliberations, the participants in the consultation came to a deeper appreciation of the continuing relevance of the Council of Nicea for the present discussion. The decisions of this council, rooted as they are in scripture and tradition, came to be regarded as normative for the whole Church.
(a) Despite differences in the method of calculation, the principles of calculation in the churches of both East and West are based on the norms set forth at Nicea. This fact is of great significance. In the present divided situation, any decision by one church or group of churches to move away from these norms would only increase the difficulty of resolving outstanding differences.
(b) The Council of Nicea's decisions are expressive of the desire for unity. The council's aim was to establish principles, based upon the scriptural data concerning the association of the passion and resurrection of Christ with the passover, which would encourage a single annual observance of Easter/Pascha by all the churches. By fostering unity in this way, the council also demonstrated its concern for the mission of the church in the world. The council was aware that disunity in such a central matter was a cause of scandal.
(c) The Nicene norms affirm the intimate connection between the biblical passover (cf. especially Exod. 12:18, Lev. 23:5, Num. 28:16, Deut. 16:1-2) and the Christian celebration of "Christ our paschal lamb" (1 Cor. 5:7). While the council rejected the principle of dependence on contemporary Jewish reckoning, it did so on the grounds that this had changed and become inaccurate, not because it regarded this connection as unimportant.
(d) In the course of their discussions the consultation also gained a deeper appreciation for the wealth of symbolism which the Nicene norms permit. In the worship of many of the churches, especially in the biblical readings and hymnography of the paschal season, Christians are reminded not only of the important link between the passover and the Christian Easter/Pascha but also of other aspects of salvation history. For example, they are reminded that in Christ's resurrection all creation is renewed. Some early Christian sources thus linked the Genesis account of the seven days of creation with the week of Christ's passion, death and resurrection.
(e) The Council of Nicea also has an enduring lesson for Christians today in its willingness make use of contemporary science in calculating the date of Easter. While the council sought to advance the concrete unity of the churches, it did not itself undertake a detailed regulation of the Easter calculation. Instead it expected the churches to employ the most exact science of the day for calculating the necessary astronomical data (the March equinox and the full moon).
As far as my claims the World Council of Churches is a front organization for bringing Protestant churches back under the control of Rome, here's a Roman Catholic priest telling us that openly-
And? If you have two different calendars and you want to unite on a day to celebrate you need to pick a day. Options are same day of the week, same day of the month, same day of the solar year. Which is “right”? The Church decided day of the week being Sunday as the new covenant following the lunar based Passover was when they wanted to celebrate it.
If you have a solar based calendar because you secretly worship the sun, and you want to make sure your day of worship falls as close to the spring equinox as possible, you do exactly what the Roman Catholic Church did.
It’s an artifact of combining the Jewish Lunar and Catholic Gregorian Solar Calendars. Passover always starts on the first full moon after the first new moon after the spring equinox. Easter is always celebrated on Sunday and because the Last Supper fell on a Thursday night (Friday for the Jews because they start the day at sunset) then Easter is always on the Sunday after Passover.
That's the Fact Check version, friend.
The Roman Catholic Church was upset some Christian churches still disregard the Council of Nicaea and dare to celebrate Easter on Nisan 15 AKA Passover, or on the Sunday following Passover. So, in 1997, the World Council of Churches, a front organization for bringing the Protestants back under Rome, gathered all of the Christian member denominations together and tried to hash out a common date, which would basically be the Roman Catholic date. Read 10. (e) below and you'll see the importance of the spring equinox to the Roman Catholic Church and their refusal to budge on that.
I won't quote the entire document but you can click on the link below to verify my summary of points 1-6.
Towards a Common Date for Easter
World Council of Churches / Middle East Council of Churches Consultation
Aleppo, Syria
March 5 - 10, 1997
Historical background to the present differences
The New Testament indicates that Christ's death and resurrection were historically associated with the Jewish passover, but the precise details of this association are not clear. According to the synoptic gospels, Jesus' last supper was a passover meal, which would place his death on the day after passover, while according to John his death occurred on the day itself, indeed at the very hour, when the paschal lambs were sacrificed. By the end of the 2nd century some churches celebrated Easter/Pascha on the day of the Jewish passover, regardless of the day of the week, while others celebrated it on the following Sunday. By the 4th century, the former practice had been abandoned practically universally, but differences still remained in the calculation of the date of Easter/Pascha. The ecumenical council held at Nicea in 325 AD determined that Easter/Pascha should be celebrated on the Sunday following the first vernal full moon. Originally passover was celebrated on the first full moon after the March equinox, but in the 3rd century the day of the feast came to be calculated by some Jewish communities without reference to the equinox, thus causing passover to be celebrated twice in some solar years. Nicea tried to avoid this by linking the principles for the dating of Easter/Pascha to the norms for the calculation of passover during Jesus' lifetime.
While certain differences in the mechanics of determining the date of Easter/Pascha remained even after Nicea, which occasionally resulted in local differences, by the 6th century the mode of calculation based on the studies of Alexandrian astronomers and scholars had gained universal acceptance. By the 16th century, however, the discrepancy between this mode of calculation and the observed astronomical data was becoming evident. This led to the calendar change introduced by Pope Gregory XIII in 1582. Since that time, western Christians have come to calculate the date of Easter on the basis of this newer Gregorian calendar, while the eastern churches generally have continued to follow the older Julian calendar. While calendrical changes in some of the Orthodox churches in 1923 affected fixed-date feasts, the calculation of the Easter date remained linked to the Julian Calendar. Our present differences in calculation of the date of Easter thus may be ascribed to differences in the calendars and lunar tables employed rather than to differences in fundamental theological outlook.
In its study of the mechanics of the paschal calculation, the consultation took note of the fact that both the current eastern (Julian) and the current western (Gregorian) calculations diverge in certain respects from the astronomical data as determined by precise scientific calculation. As is well known, the Julian calendar at present diverges from the astronomical by thirteen days; the Gregorian at present does not diverge significantly, though it will in the distant future. Less well known is the fact that both Julian and Gregorian calculations rely upon conventional tables for determining the lunar cycle. For both modes of calculation, these tables at times give results that diverge from the astronomical data.
The continuing relevance of the Council of Nicea
(a) Despite differences in the method of calculation, the principles of calculation in the churches of both East and West are based on the norms set forth at Nicea. This fact is of great significance. In the present divided situation, any decision by one church or group of churches to move away from these norms would only increase the difficulty of resolving outstanding differences.
(b) The Council of Nicea's decisions are expressive of the desire for unity. The council's aim was to establish principles, based upon the scriptural data concerning the association of the passion and resurrection of Christ with the passover, which would encourage a single annual observance of Easter/Pascha by all the churches. By fostering unity in this way, the council also demonstrated its concern for the mission of the church in the world. The council was aware that disunity in such a central matter was a cause of scandal.
(c) The Nicene norms affirm the intimate connection between the biblical passover (cf. especially Exod. 12:18, Lev. 23:5, Num. 28:16, Deut. 16:1-2) and the Christian celebration of "Christ our paschal lamb" (1 Cor. 5:7). While the council rejected the principle of dependence on contemporary Jewish reckoning, it did so on the grounds that this had changed and become inaccurate, not because it regarded this connection as unimportant.
(d) In the course of their discussions the consultation also gained a deeper appreciation for the wealth of symbolism which the Nicene norms permit. In the worship of many of the churches, especially in the biblical readings and hymnography of the paschal season, Christians are reminded not only of the important link between the passover and the Christian Easter/Pascha but also of other aspects of salvation history. For example, they are reminded that in Christ's resurrection all creation is renewed. Some early Christian sources thus linked the Genesis account of the seven days of creation with the week of Christ's passion, death and resurrection.
(e) The Council of Nicea also has an enduring lesson for Christians today in its willingness make use of contemporary science in calculating the date of Easter. While the council sought to advance the concrete unity of the churches, it did not itself undertake a detailed regulation of the Easter calculation. Instead it expected the churches to employ the most exact science of the day for calculating the necessary astronomical data (the March equinox and the full moon).
https://www.oikoumene.org/resources/documents/towards-a-common-date-for-easter
As far as my claims the World Council of Churches is a front organization for bringing Protestant churches back under the control of Rome, here's a Roman Catholic priest telling us that openly-
https://catholiccourier.com/articles/catholic-church-not-full-member-of-wcc-but-works-in-partnership/
And? If you have two different calendars and you want to unite on a day to celebrate you need to pick a day. Options are same day of the week, same day of the month, same day of the solar year. Which is “right”? The Church decided day of the week being Sunday as the new covenant following the lunar based Passover was when they wanted to celebrate it.
If you have a solar based calendar because you secretly worship the sun, and you want to make sure your day of worship falls as close to the spring equinox as possible, you do exactly what the Roman Catholic Church did.