(Exodus 13:6) "And on the seventh day, a festival to the L–rd": Perhaps wherever chagigah (the festival offering) obtains, (the mitzvah of) matzoh obtains, but when chagigah does not obtain (i.e., when there is no Temple), there is no matzoh? It is, therefore, written (Ibid. 7) "Matzoth shall be eaten the seven days" (in any event).