Once
a tzurah loses it's form and becomes chomer, it can no longer be restored
to its original tzurah. The gemara in Bava Kamma [96b] teaches that if one
steals a brick and turns it into dust, he acquires it [as it is no longer the brick that he stole]. Even though he
could refashion the dust and turn it into a brick it would not be the same
brick it originally was but rather "panim chadoshos". We see from this that "once a tzurah - always a tzurah" is not a guiding principal. Au contraire. Once it loses its tzurah - that is it.
A sandal from which one ear broke off and he repaired it, it is still tamei medras. If the second ear broke off and he repaired it, it becomes tahor from tumas medras [but remains tamei as having TOUCHED a medras].
The gemara asks: Why is it that when the first ear broke the sandal remains tamei as a medras? Is it because the second ear is intact and the sandal is still usable? When the second ear breaks the sandal should also remain tamei medras because the first ear is already repaired and the sandal is still usable? Answers the gemara - When both ears have broken, a "new face" [פנים חדשות] has come into being here. [Shabbos 112b]
Once it loses its tzurah [i.e. both ears broke off] - that's it. פנים חדשות באו לכאן!
It
says that Hashem restored the sea after splitting it לאיתנו [to its strength]
which is the same letters as לתנאו. Meaning, Hashem kept his "condition" [tnai] with
maaseh breishis that the sea would split. Even after the sea split there was no
true change in the tzurah because it was all part of the original plan. If it
would have been a bona-fide shnui tzura then it would have required a new
creation to restore it to it's original state [because once changed -
"tzuros" can't be restored without a new creation]. Since Hashem
doesn't create new things after that six days of creation – we would be in
trouble…. The sea would have to remain split. Therefore, Hashem made this
condition enabling the sea to return to its original state.
[Based on the Rogochover]
לזכות נעכא גיטל בת רחל אסתר זרעא חיא וקיימא זרעא די לא יפסוק ודי לא יבטול מפתגמי אורייתא
