When did the Last Supper take place?
Synoptics: On the Passover ([Matt. xxvi, 18–20]; [Mark xiv, 16–18]; [Luke xxii, 13–15]).
John: On the day preceding the Passover.
Luke says: “And they made ready the passover. And when the hour was come, he sat down, and the twelve apostles with him. And he said unto them, With desire I have desired to eat this passover with you before I suffer.”
John, in his account of the Last Supper, says it was “before the feast of the passover” ([xiii, 1]). The Evangelists all agree that his trial and execution took place on the day following the Last Supper. John says the Jews “went not into the judgment hall, lest they should be defiled; but that they might eat the passover” ([xviii, 28]). After narrating the events of the trial, John says: “And it was the preparation of the passover” ([xix, 14]).
According to the Synoptics, the Last Supper was eaten on the 14th Nisan, and, by our mode of reckoning time, on Thursday evening; according to John, it was eaten on the 13th Nisan, and, by our mode of reckoning, on Wednesday evening. The Synoptics declare that this supper was the regular Paschal meal; according to John, it was an ordinary meal, the Paschal meal not being eaten until after Christ’s death.
“The Synoptics represent most clearly that Jesus on the evening of the 14th Nisan, after the custom of the Jews, ate the Passover with his disciples, and that he was arrested in the first hours of the 15th Nisan, the day on which he was put to death. Nothing can be more distinct than the statement that the last supper was the Paschal feast.... The fourth Gospel, however, in accordance with the principle which is dominant throughout, represents the last repast which Jesus eats with his disciples as a common supper, which takes place, not on the 14th, but on the 13th Nisan, the day ‘before the feast of the Passover.’”—Supernatural Religion.
Thousands of pages have been written in vain attempts to reconcile this grave discrepancy. Scribner’s “Bible Dictionary,” which contains the best fruits of orthodox scholarship, both of England and America, concedes a contradiction. It says: “The Synoptics seem to identify the two [the Last Supper and the Paschal meal], whereas St. John expressly places the Last Supper before the Passover.”
After an exhaustive review of the subject, Strauss voices the conclusion of German scholars in the following words: “Our only course is to acknowledge an irreconcilable contradiction between the respective accounts, without venturing a decision as to which is the correct one” (Leben Jesu, p. 702).