Are you saying the preparation day (the day they kill the Passover lamb) is the 13th, or 14th of Nisan?
The two evenings recorded in the Hebrew book of Exodus, were between midday, the first evening, when the sun began its descent toward the horizon, with the second evening being the twilight, immediately before the sun disappears.
From the Jerusalem Bible, Exodus 12: 5-6. The Pascal lamb must be an animal without blemish, a male one year old, you may take it from either sheep or goat. You must keep it till the 14th day of the month when the whole assembly of the community of Israel shall slaughter it between the two evenings, etc.
The Passover Lamb had to be eaten after the sun had set on the thirteenth day, which was the beginning of the 14th day of Passover. To slaughter thousands of animals, skin them, which includes skinning the head, hoofs and all without breaking a bone, then to gut the animal and wash clean the entrails that had to be eaten also, was not a job that would have been done in the dark.
This was the Law in the days of Moses and after.
But I have already said in another post, that the Jews later did away with the one day festival of Passover, and incorporated it into their seven day festival of Unleavened Bread.
Numbers 28: 16; The Passover festival in honour of the Lord, is to be held on the fourteenth of the first month.*
Exodus 12: 14; “You must celebrate ‘
THIS DAY’*as a religious festival to remind you of what I, the Lord have done, Celebrate it (
One day)*for all time to come.
Numbers 28:17; On the fifteenth day a religious festival begins which lasts seven days, during which, only unleavened bread is to be eaten. On the first and the last day of the seven day festival of unleavened bread, they were to gather for worship and no work was to be done on those days
The scriptures reveal how, when, and why, the day of Passover as a separate festival was abandoned.
But Jesus remained with the truth of God's word and ate the Passover meal with his disciples, in the evening of the 14th day of the first month.
The "Last Supper" was a Passover meal without a Lamb, as Jesus was the fulfilment of the Passover Lamb, and that Passover meal seems to have followed much the same order as we find in the Mishnah.
In the New Testament accounts, we find reference to the First Cup, also known as the Cup of Blessing (Luke 22:17); to the breaking of the matzoh (Luke 22:19); to the Third Cup, the Cup of Redemption (Luke 22:20); to reclining (Luke 22:14); to the charoseth or the maror (Matthew 26:23), and to the Hallel (Matthew 26:30).
In particular, the matzoh and the Third Cup are given special significance by Jesus:
And he took bread, gave thanks and broke it, and gave it to them, saying, "This is my body given for you; do this in remembrance of me." In the same way, after the supper he took the cup, saying, "This cup is the new covenant in my blood, which is poured out for you" (Luke 22:19-20)
Later that night Jesus was sentenced to death by Pilate at midnight, on the day of preparation to the Jews Passover which had been incorporated into their first day of the festival of Unleavened Bread, he was nailed to the cross at 9 AM and died at 3 PM, between the two evenings of the day of preparation to their Passover.