Also, by the First Century the word Peshach/Pascha was being used for all the Nisan Holy Days together and not just 14th which is the Proper Torah terminology, but this looser application is perhaps anticipated by Ezekiel 45 21-24. That's why in Acts 12 it's still Pascha after the Days of Unleavened Bread have started.
First I want to discuss how the Quartodecimanism debate that went on in the Second Century was not the same thing as the arguments modern Hebrew Roots/Torah Observant Christians have with mainstream Western Christianity, or even the same thing as the debate that was had at the Council of Nicaea.
Both sides of the original Quartodeciman controversy were using the same calendar, and it seems like it was a lunar Calendar, if it was exactly the same Calendar the Jews of the time were using or not I don't know for sure but I think it probably was. The debate was about whether the main celebration (Feast being the word used) should be on the 14th of Nisan (the position of the Quartodecimans) or the following Sunday which seems to be what most Christians were doing. The Sunday observers fasted through the 14th till Sunday morning.
It wasn't a debate between two entirely different methods of when to calculate anything, but a debate about whether the day Jesus was Crucified, or the Day He Rose from the Dead should be the day of the Feast. Or in the context of Leviticus 23, Exodus 12 and Numbers 28, the day the Passover Lamb is killed or First Fruits, which is always on the morning after the Sabbath hence Sunday.
Modern Torah observant Christians often assume the Quartodecimans were the ones on their side of the dispute, and anyone who wanted to do anything but hide under their beds on a Sunday must have been closet Pagan sun worshipers.
The truth is both sides of the dispute were adding to the Torah by seeing a full Fast as being required at all. But if you read Leviticus 23 more closely, specifically verses 9 through 14 which are about First Fruits. Verse 14 says.
"And ye shall eat neither bread, nor parched corn, nor green ears, until the selfsame day that ye have brought an offering unto your God: it shall be a statute for this age throughout your generations in all your dwellings."So, it sounds like a fast of sorts ends on First Fruits. It's also interesting that Esther's fast was at the time when Passover would normally be celebrated, but it lasted three days trough the 14th and 15th days of the month, leading to her final victory on the 17th.
Melito of Sardis' Passover teaching clearly teaches the Torah being done away with, so no the Quartodecimans were not the Hebrew Roots people of their time.
To Christians the two most important events in history are the Crucifixion and Resurrection of Jesus Christ. I would argue that the Resurrection is more important, in the Sermon on Mar's Hill in Acts 17 Paul's presentation of The Gospel to a gentile audience does not directly refer to the Death of Jesus at all, but the climax is definitely The Resurrection. In 1 Corinthians 15 Paul refers to both the Crucifixion and the Resurrection at the beginning, but the rest of the chapter is primarily about the Resurrection.
Crucifixion Day is a day to mourn (which is often an appropriate time to Fast in Jewish thought), The Resurrection is what we celebrate.
Polycrates_of_Ephesus defended the Quartodeciman position by citing the long established traditions of the Churches in Asia. But I've already talked about how The Bible itself gives us reasons to suspect that region was where things first started going wrong.
The debate about Easter at the Council of Nicaea is also highly misunderstood. This debate was only about first if Christians should use the same Lunar Calendar as the Jews, and then if all Churches should use the same calendar. There was not even any disagreement that it should be a Lunisolar Calendar.
The Council's final decision was that it should be determined independent of the Jewish calendar, and that there should be a universal agreement. But what that final calendar was took a long time to form.
And it wasn't till centuries later that the Roman Church started making a deliberate effort to make sure Christian Passover never lines up with Jewish Passover, doing that is arguably just as much in violation of Nicaea's decision as adopting the Jewish reckoning would be, since that's not a truly independent decision.
Nicaea was addressing a disagreement that began in the late 3rd Century, so it predated Constantine's influence but was still a century after the Quartodeciman controversy.
One of the arguments against the Jewish Reckoning made at this time was that it sometimes had Passover happening before the Spring Equinox. Now that makes it seem to me like a form of the modern Rabbinic Jewish calendar is what they were breaking with here, and indeed it seems to have developed at the same time this Christian disagreement started. The modern Kariate reckoning has if anything the opposite problem, a tendency to happen maybe a little too long after the Equinox. My current opinion is that Nisan should begin with the Crescent New Moon closest to the Spring Equinox, whether it's before or after..
Did the Church's developing Anti-Semitism play some factor in why this happened? Possibly, but just as Anti-Semites criticizing Israel doesn't make criticism of the Israeli Government inherently Anti-Semitic, there is likewise disagreement even among Jews on if the Rabbinic calendar is correct.
I'm not a legalist, I don't think it's a big deal if we're technically observing things on the wrong day. But I wanted to clarify how neither of these disputes were an Ancient Hebraic Christian practice being suppressed by a Solar Calendar using organized Church. The origin of the current method the Roman Catholic Church and most Protestant Churches use is much longer and more complicated.
