One of the things that unites Jewish communities around the world is that we read the same passage from the Torah each week. Chanted in full, in Orthodox synagogues, or read more slowly, abridged and translated in Progressive ones, we keep in step as we make our yearly way through the Torah.

When Eighth Day Pesach falls on Shabbat, however, the unity frays a little. In Israel there are only seven days of Pesach, so this Shabbat is already oys yontef ("after the festival") and the sidrah is Acharei Mot. Liberal Jews, too, keep just seven days of Pesach, so we will be reading Israeli-style. Right up to August 6, when the diaspora doubles up Mattot-Massei, Israel and chutz la'aretz, Orthodox and Progressive, will be a week out of step with each other. And we'll manage.

The haftarah for Eighth Day Pesach is the great messianic passage of Isaiah 11-12, a vision of a perfected, peaceful world where "the wolf will dwell with the lamb, the leopard lie down with the kid" (Isaiah 11:6). This verse divided the greatest Jewish thinkers. For the mystically inclined, like Nachmanides, it points to a miraculous transformation of nature. The rationalist Maimonides, on the other hand, insists that it is a metaphor and simply means that Israel will dwell at peace among the nations.

Some might think that the greatest miracle, though, comes a few verses later, when the prophet speaks of the divided tribes of Israel living peacefully together, without envy and harassment. Ephraim and Judah symbolise the warring northern and southern kingdoms of ancient Israel, the ten lost tribes and the Judean exiles, all returning and being reconciled after their long estrangement.

We modern tribes of Israel may be out of step with one another in some ways, but if we can live together without envy and harassment, we will help at least a bit of the messianic vision to become reality.