The feast of the Passover, when Yeshua knew that his hour was come that he should depart out of this world unto the Father, having loved his own which were in the world, he loved them unto the end. – John 13:1
A question arises as to when Yeshua, the firstborn, kept the Passover meal, as John’s gospel seems to record it being the evening before the actual Passover when the lambs were slain, and the seder meal eaten. Here is a possible explanation, which provides for the Torah command to not rejoice over the death of enemies, being that some 22,000 firstborn males died in the final plague on Egypt at the first Passover in place of some 22,000 firstborns in Israel: “Fast of the Firstborn (Hebrew: תענית בכורות, Ta’anit B’khorot or תענית בכורים, Ta’anit B’khorim); is a unique fast day in Judaism which usually falls on the day before Passover. Usually, the fast is broken at a siyum (conclusion of the fast) celebration (typically made at the conclusion of the morning services), which, according to prevailing custom, creates an atmosphere of rejoicing that overrides the requirement to continue the fast. Unlike most Jewish fast days, only firstborns are required to fast on the Fast of the Firstborn.” That meal the evening before the Passover seder is called today, among orthodox Jews, seudat hamashiach- the Meal of the Messiah.
The Shabbat is not reckoned only on the seventh day of the week (Saturday), but every festival of YHVH is a Sabbath, which may fall on any day of the week. For the words of Yeshua to have meaning that he would be in the tomb for three days and three nights, his Passover meal would take place on Wednesday evening the beginning of 13th of Nissan (as in Genesis, the day begins in the evening), his arrest after the meal at Gethsemane, on Thursday morning taken before the Roman Pilatus and sent to be crucified on the 13th of Nissan (the Preparation Day- John 19:31; 42), his death as the Passover lambs were beginning to be sacrificed on the eve between the 13th and 14th, laid in the tomb through the High Sabbath (Shabbat hagadol) of the day of Passover on the 14th, and remain in the tomb through Friday until after the 7th day Shabbat, making three days and three nights. Miriam came to the tomb after the 7th day Sabbath which ends Saturday at sundown, arriving “early on the first day of the week while it was still dark”- on the festival of Firstfruits, the first day of the counting of the Omer (Leviticus 23:10-14), and found the tomb already empty. ”But now is Messiah risen from the dead, and become the firstfruits of them that slept”- (1 Corinthians 15:20).