Summary: This is a study on the subject of what day of the week was Jesus crucified to fulfill the prophecy He spoke about Himself in Matt. 12:40.
So if Jesus was crucified during the week when the Passover and Feast of the Unleavened Bread were going to be celebrated, and the first day of the Feast of the Unleavened Bread was also a Special Sabbath day. This means that there was more than one Sabbath occurring during that week. A special Sabbath for the first day of the Feast of Unleavened Bread, and then the regular weekly Sabbath on Saturday.
Look again at John 19:31 (quickview)  which talks about the crucifixion day. It says, “Now it was the day of Preparation, and the next day was to be a special Sabbath. Because the Jews did not want the bodies left on the crosses during the Sabbath, they asked Pilate to have the legs broken and the bodies taken down.”
See that phrase “a special Sabbath”? In the English Standard Translation it says, “for that Sabbath was a high day.” This passage is saying that Christ was crucified on the day before the special Sabbath, which occurred on the first day of the Feast of Unleavened Bread, not on the day before the regular weekly Sabbath.
To me this passage is clearly saying that Christ WASN’T crucified on the Friday before the regular weekly Sabbath, but instead on the day before or the preparation day leading up to the beginning of the Feast of the Unleavened Bread.
Likewise, take another look at Matthew 28 (quickview) : 1, which says, “After the Sabbath, at dawn on the first day of the week, Mary Magdalene and the other Mary went to look at the tomb.” The Greek word for “sabbath” in this instance is plural meaning more than one. So, according to this verse, Jesus rose from the dead after two Sabbaths had occurred.
Date of Feast of Unleavened Bread
So, if Jesus was crucified on the day preceding the Feast of the Unleavened Bread that begs the next logical question: On what day of the week did the Feast of the Unleavened Bread begin?
Well, I wish I could say that it occurred on the same day of the week every year like our holiday of Thanksgiving does. If it did, we’d have a definitive answer. Unfortunately, it’s not that easy. Because the Feast of Unleavened Bread begins on the same day of the month each year, and not the same day of the week.
Leviticus 23:5-6 (quickview) , “The Lord’s Passover begins at twilight on the fourteenth day of the first month [Nisan].  On the fifteenth day of the month the Lord’s Feast of Unleavened Bread begins…” The first month of the Jewish year is called Nisan and it coincides with our months of March and April.
Now, knowing that this Feast begins on Nisan 15th, and knowing that Jesus was crucified the day before it began, we do have a date for the crucifixion, which is Nisan 14th, the day of Passover.
Resurrection Date to Crucifixion Date
Now, since no one can seem to agree on the exact year that Jesus was crucified it’s impossible to track down on what weekday Nisan 14th occurred the year He was crucified. But we can use this date to help us figure out the day of Resurrection, which we already know occur on a Sunday morning. (This is kind of like one of those logic puzzles in those puzzle books you can find in stores. – I always did like logic puzzles.)