22 The words “for the feast” are not in the Greek text, but have been supplied for clarity.
23 Generally the feast of Unleavened Bread would refer to Nisan 15 (Friday), but the following reference to the sacrifice of the Passover lamb indicates that Nisan 14 (Thursday) was what Luke had in mind (Nisan = March 27 to April 25). The celebration of the Feast of Unleavened Bread lasted eight days, beginning with the Passover meal. The celebrations were so close together that at times the names of both were used interchangeably.

In other versions

Then came the day of Unleavened Bread, on which the Passover lamb had to be sacrificed.

Then came the day of Unleavened Bread on which the Passover lamb had to be sacrificed.

Then the Day of Unleavened Bread came when the Passover lamb had to be sacrificed.

Now the Festival of Unleavened Bread arrived, when the Passover lamb is sacrificed.

And the day of the feast of Unleavened Bread came, on which it was necessary for the Passover lamb to be sacrificed.

Then came the day of unleavened bread, when the passover must be killed.

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