Passover – 14th or 15th?
Why is it that Passover is celebrated worldwide beginning on the night of the 15th of Nisan? The Torah states a number of times that the Passover celebration falls on the 14th day of the first month (e.g. Exodus 12:6, Leviticus 23:5, Numbers 9:3). And to my knowledge, in the Jewish calendar the day follows the night. Thus, the Seder should be celebrated on the eve of the 14th, but Jews universally celebrate in on the 15th. Why is that?
The Aish Rabbi Replies
Thank you for your interesting question. You are right that the Torah makes mention of a holiday on the 14th of Nisan. But interestingly, that is a separate holiday from Passover, which begins on the 15th. If you read Leviticus 23:5-6 carefully, you will see that there are actually two holidays at this time:
(a) “Pesach” – the slaughtering and eating of the paschal lamb (or goat) which begins the afternoon of the 14th with its slaughtering and continues that night with its consumption.
(b) “The Holiday of Matzot” – the seven day feast we refer to as Passover, which begins the night of the 15th.
Today, without our holy Temple, we do not bring the Passover offering. Thus, the only holiday relevant to us is Passover itself which begins on the 15th. Even so, the 14th is still considered a minor holiday – mainly in commemoration of the ancient holiday, where many have the custom not to work (beyond Passover preparations) and there is likewise a custom to study the laws of the Passover offering (Shulchan Aruch O.C. 46:8:1-3, Mishna Berurah 1).
Another relevant point is that although in most areas of Jewish law, a “day” begins the evening before, for Temple service the night follows the day. This is as the Temple offerings of the day would often be burned or consumed the night after (and many would become invalid the next day). Thus, the holiday of "Pesach" actually began the day of the 14th, ending the night of the 15th.
(Basic approach heard from my teacher R. Yochanan Zweig.)