Conflicting Passover Chronologies?

For some biblical skeptics, one alleged proof for the falsity of the Gospel narratives is the apparent contradiction in when Jesus was put to death. First, let's look at the narrative of the Last Supper from Luke 22:

Then came the day of Unleavened Bread, on which the Passover lamb had to be sacrificed. So Jesus sent Peter and John, saying, "Go and prepare the Passover for us, that we may eat it." They said to him, "Where will you have us prepare it?" He said to them, "Behold, when you have entered the city, a man carrying a jar of water will meet you. Follow him into the house that he enters and tell the master of the house, 'The Teacher says to you, Where is the guest room, where I may eat the Passover with my disciples?' And he will show you a large upper room furnished; prepare it there." And they went and found it just as he had told them, and they prepared the Passover (Luke 22:7-13).

Here we see the Passover being prepared probably on Wednesday evening but sacrificed and eaten on Holy Thursday. This is evident by our Lord's reference to the meal consumed on Holy Thursday as "this Passover" (Luke 22:15). But now let's look at the account in the Gospel of John:

Then they led Jesus from the house of Caiaphas to the governor’s headquarters. It was early morning. They themselves did not enter the governor’s headquarters, so that they would not be defiled, but could eat the Passover (John 18:28).

Here is is "early morning" on Good Friday and Passover still had not happened yet, for the Pharisees would not enter the Praetorium lest they defile themselves before the Passover. We see other things in John that suggest that the Passover still had not happened yet as of Friday afternoon:

Since it was the day of Preparation, and so that the bodies would not remain on the cross on the Sabbath (for that Sabbath was a high day), the Jews asked Pilate that their legs might be broken and that they might be taken away (John 19:31).

Here we have Jesus dying on the cross at the very time that the Passover lambs around Jerusalem would have been being slaughtered. Later, we see Jesus hastily buried so that the Jews can return to Jerusalem and celebrate the Passover for which they had been preparing:

So they took the body of Jesus and bound it in linen cloths with the spices, as is the burial custom of the Jews. Now in the place where he was crucified there was a garden, and in the garden a new tomb in which no one had yet been laid. So because of the Jewish day of Preparation, since the tomb was close at hand, they laid Jesus there (John 19:40-42).

So we are left with two chronologies: one has Jesus eating the Last Supper on the eve of the Passover, the other has Jesus dying the afternoon before the Passover even begins, which is apparently celebrated Friday evening going into Saturday. Which one of these accounts is true?

Well, the biblical skeptic quickly says that two contradictory accounts disproves the story, but the historian understands that maybe the problem is not two contradictory accounts but two Passovers.

In Israel in the first century AD there were two different Passovers being kept that were calculated using two differing calendars. The original Jewish calendar (called the "Creation" calendar) dates the beginning of a new day from the setting of the sun, based on Genesis 1 where a day is defined as the time from when the sun rises to when it sets, based on a separation between darkness and light. All of the original mandates for the Feasts in the Old Testament were based on this understanding of the calendar. So for the Creation calendar, a new day is commenced at sunrise, and furthermore, a new month is commenced at the beginning of a new moon (see Numbers 28:14; 1 Samuel 20; Isaiah 66:23).

But when the Romans came into Palestine they introduced a differing calendar, one where a new day was reckoned from midnight. Thus a Wednesday night and Thursday morning share the same darkness but midnight splits the night into two dates. Another factor is that while in Babylon, the Jews adopted the practice of reckoning the new months not from the new moon but from the sighting of the first crescent of a new moon.

After the return from Babylon, the Jews nationally used the Babylonian system to determine when Passover should begin. This was the national Passover that was kept by the Pharisees, Temple authorities and most Jews that took place the evening of Good Friday going into Holy Saturday, as recorded in the Gospel of John. Since John was a relative of the High Priest and educated in the Temple establishment, he would have naturally regarded the later Passover as the true Passover.

But the Jews were divided on the date of the observance of Passover. Some Jews insisted on following Creation’s calendar, that is, Nisan 1 began on the day of a new moon. Jewish leaders, however, insisted on using the Babylonian method for determining the first day of each month. The High Priest waited until the first crescent of the new moon was sighted before declaring the commencement of Nisan 1. Because the conjunction of a new moon and the sighting of the first crescent of a new moon in Jerusalem is typically 16 to 40 hours later, the celebration of two Passovers on two different days in Israel was not uncommon. Many Jews regarded the date of the Passover as celebrated by the High Priest to be sacriligious, and continued to keep the Passover according to the Creation calendar, which would have been celebrated on Holy Thursday night. Among other groups that kept this Passover were the Essenes and any conservative Jew who dissented from the Pharisaical establishment.

Three things of interest:

First, Jesus chose to celebrate the Passover according to the Creation calendar, not the Temple calendar. This may suggest an implicit approval of this calendar, but it may also be a prophetic way to fulfill both the sacrificial and sacerdotal elements of His offering: in the Passover of Holy Thursday we see him officiating and offering the Passover; the following day, we see Him as the victim, being killed while all the Passover lambs are being slain in Jerusalem. Both are fitting.

Second, one reason the Jews rejected the Temple dating is because it was predicted in Daniel that in the time of the Antichrist (or, the "Abomination" in the language of that book) that the dates and times of feasts would be altered:

After them another king will arise, different from the earlier ones; he will subdue three kings. He will speak against the Most High and oppress his saints and try to change the set times and the laws (Daniel 7:24-25).

This did in fact happen in first century Judea, and it did in fact herald the coming of the Messiah and the destruction of the Temple.

Third and finally, it was common knowledge in the ancient world that the Jews celebrated two Passovers. This fact was even noted by the Emperor Constantine, who took it as evidence against the veracity of the Jewish calendar when looking to determine the date of Easter:

"They [the Jews] do not possess the truth in this Easter question; for in their blindness and repugnance to all improvement, they frequently celebrate two Passovers in the same year" (Eusebius, Vita Const., Lib iii., 18-20).

Therefore, as with the case with the Resurrection chronology of Jesus, we need not worry about alleged contradictions in the Gospels. The multiple times given for the Passover in the Gospels are not due to inconsistencies or untruths on the part of the Evangelists but rather to the existence if divergent dates for celebrating the Passover in ancient Israel.