Question: ...How could Jesus be the Messiah the Lamb, if He was not crucified until a day after the ...

Question: Mark:14:12And the first day of unleavened bread, when they killed the passover, his disciples said unto him, Where wilt thou that we go and prepare that thou mayest eat the passover?
See All... says, “And the first day of unleavened bread, when they killed the passover, his disciples said unto him, where wilt thou that we go and prepare that thou mayest eat the passover?” Later that night he was betrayed. So how could Jesus be the Messiah the Lamb, if He was not crucified until a day after the passover lamb was slain? Mark:15:1And straightway in the morning the chief priests held a consultation with the elders and scribes and the whole council, and bound Jesus, and carried him away, and delivered him to Pilate.
See All... says, “in the morning,” so it had to be the next day, a day after the passover, that Jesus was slain.

Response: I have answered that question in previous newsletters (the most recent being in June 2000) and in my books, but will do so here briefly once more. The Jewish day begins at sunset, thus it begins with night, followed by morning, and the following afternoon is called the evening. The day “when they killed the passover,” 14 Nisan, began after sunset Wednesday. That night the last supper was eaten. The passover lamb was not slain until the following afternoon in the evening of 14 Nisan (Ex 12:6), before sunset marked the beginning of 15. Then the lamb would be roasted and that night (v 8), after sunset and thus 15 Nisan, it would be eaten.

The fifteenth was the first day of the seven-day feast of the passover and unleavened bread and was a “high sabbath.” Thus John states that when Jesus was on the cross “it was the preparation of the passover [i.e., the lambs were being slain],” and explains further, “The Jews therefore, because it was the preparation [of the passover], that the bodies should not remain upon the cross on the sabbath day (for that sabbath day was an high day), besought Pilate that their legs might be broken, and that they might be taken away.” In A.D. 32 when Jesus was crucified, the high Sabbath went from Thursday evening to Friday evening, followed by the weekly sabbath from Friday evening to Saturday evening, so the women could not get to the grave until Sunday morning.

The last supper was held “before the feast of the passover” (Jn:13:1-2 [1] Now before the feast of the passover, when Jesus 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. [2] And supper being ended, the devil having now put into the heart of Judas Iscariot, Simon's son, to betray him;
See All...), on the night of 14 Nisan in the upper room where the disciples began their preparation. The passover lamb would be slain the following afternoon (the evening of 14 Nisan) and eaten that night. But Jesus would not participate because He would be betrayed right after the last supper, brought before the rabbis, then taken by them early in the morning of the fourteenth to Pilate and finally crucified in the afternoon (evening) of 14 Nisan just when Israel’s passover lambs were also being slain.

The morning (14) following the last supper when the rabbis took Jesus to Pilate, no one in Israel (including Christ and His disciples) had eaten the passover because the lambs would be slain that afternoon (at the same time Jesus was crucified): “...they themselves went not into the judgment hall, lest they should be defiled; but that they might eat the passover” (Jn:18:28Then led they Jesus from Caiaphas unto the hall of judgment: and it was early; and they themselves went not into the judgment hall, lest they should be defiled; but that they might eat the passover.
See All...). I hope this clarifies it.