Az yashir Moshe- Az is gematria 8! When did they sing, only after Am Israel started to believe in Moses, after they saw the bodies of their masters floating up on the shores symbolizing that they were no longer slaves of the Egyptians. M-emouna means "faith" Rabbi Israel wrote a whole book about this VERY important prerequisite to all the mitsvotes, and to simcha and to Tikkun ha Bris (which is symbolized by the eigth day is it not?). Memouna- Menora the eigth light which purifies miraculously can only be the light of the unblemished Tzaddik.
Shemo-Na Na8. Shem "N".
In KI Tissa (because you will raise) You find IM Tissa (If you will raise) 32.32 Names with the famous phrase "If you raise their signature and if not erase me from your book you wrote" In reverse "I am Nachman".
The real Pessach could not occure until Na Nach was revealed and the Memouneh became a national Israeli Holiday like Hannukka and Purim.