back where we started from -- or (hopefully) not; interesting chiddush of the Ben Ish Chai re: isru chag

1) Chazal tell us that not only did Yam Suf split to allow Bn"Y to cross, but all the waters in the world split as well.  Some explain that water symbolizes all of our troubles.  הושיעני אלקים כי באו מים עד נפש (Teh 69).  Shevi'i shel Pesach is not just about getting across the particular obstacle of Yam Suf, but is about being able to get across all of the obstacles and difficulties in our path.

Some have the custom to stay up all night learning.  I want to suggest that water also symbolizes, as it does many other places, אין מים אלא תורה.  You are stuck on a difficult Tos?  You are breaking your head on a R' Akiva Eiger?  Shevi'i shel Pesach is for you.  You can break through the difficulty and get to the other side.

2) According to Tos (Archin 15) Bn"Y did not cross the Yam Suf from one side to the other, but made rather traverssed the sea in a U shape path to end up back on the same side that they started out on.  Even though Bn"Y ended up back where they started from, they had undergone a sea change (pun intended) in the course of their journey.  The Egyptians who had persecuted them were finally destroyed completely, never to haunt them again.  My wife suggested that this is the lesson of shevi'i shel Pesach.  We may find ourselves at the end of the chag back where we started from -- the same home, the same job, the same challenges and pressures -- but hopefully we have undergone change over the past week and are not the same people coming out of the chag that we were going in.

3) R' Shternbruch in his teshuvos (vol 2 #321) quotes an interesting chiddush of the Ben Ish Chai that on isru chag one should wear bigdei shabbos and only do melacha necessary for davar ha'aveid, like chol ha'moed.  I don't know if anyone accepts this shita l'halacha (I asked a Sefardi Rav yesterday about it and he was unfamiliar with this view), but even if it not lmaaseh, we can still take the message with us of clinging to the orot of the chag as it departs from us and not being too quick to rush back into the turmoil of the mundane world.