On the Date of the Passover mentioned in the Gospel

There can be a difference of one day or four weeks or four weeks and one day. in the date of Passover. If the Passover is calculated from a starting-point for the first day of the first month that requires direct sighting of the New Moon, as opposed to calculation, then the date by the first method will often be one day later. Also, there are some differences that I don’t understand between the Samaritan and Rabbinic astronomical calculation systems, so that the Rabbinic Passover is sometimes a day late, as it was this year. Besides this, the Rabbanite system intercalates a leap month of 28 days at the end of every eighth year to keep the sun and moon in line, whereas the Samaritan system is different in not intercalating a whole month. I don’t understand either system fully. There was an intercalated month before the Passover of 33 A.D. Notice that the intercalated month in the Rabbinic system won’t change the day of the week of Passover, since it has 28 days. The system of calculation used by the Samaritans is ancient. The Dositheans did not have this system. We don’t know whether they had a different system or whether they depended on observation of the New Moon. We don’t know what they did about intercalation. The Karaites required direct observation originally, but I think they now use a calculation method, not the same as the Rabbanite one. Anyway, any group using direct observation must have a calculation system in case it is overcast on the night of the first of the first.

Days of the week of the Rabbinic Passover.
In 30 A.D. the sunset starting the 15th of the first month fell during Wednesday 6th April.
31 A.D. Monday 27th March.
32 A.D. Monday 16th April.
33 A.D. Friday 4th April.
34 A.D. Monday 24th March.
35 A.D. Monday 12th April.
36 A.D. Friday 31st March.
37 A.D. Wednesday 22nd March.
38 A.D. Monday 8th April..
39 A.D. Friday 29th March.
40 A.D. Friday.17th April.
41 A.D. Monday 4th April.

Notice that NONE of these days is a Thursday. This disposes of a lot of futile speculation about the supposed difference in dating Passover between John and the Synoptic Gospels.

The Last Supper was not an observance of Passover. The mention of Passover by Jesus on Thursday night, just after the sunset marking the start of the 14th, is no more than a reference to what is to be done the next day in preparation. If Jesus had entered Jerusalem on the 14th, he would have been unable to attend to the preparation. Also, if he had entered on the 14th and the Last Supper had been the Seder at the start of the 15th, the Passover lambs would already have been slaughtered that afternoon. I really wish N.T. scholars would (a) learn a bit about Judaism, and (b) learn to think straight.

Definition as before. The day on which the sunset marking the start of the 15th of the first falls.
24 A.D. Wednesday 13th April.
25 A.D. Monday 3rd April.
26 A.D. Friday 24th March.
27 A.D. Wednesday 10th April.
28 A.D. Monday 30th March.
29 A.D. Saturday 17th April.

There are calendars in which the festivals fall on fixed days of the week. This includes the Qumran calendar. The Samaritan (but not Dosithean), Qumran (I think), Sadducaean, Christian, and some calendars reflected in the Versions always set Pentecost on a Sunday i.e. starting at sunset on Saturday. I don’t know whether any calendars always set Passover on a Friday. The Sadducees seem to have agreed with the Pharisees that it could fall on several different days.