RAMADAN: What incident in Islam is more Important- I THINK THE DAY OF PERFECTION OF DEEN?

QURAN 5:3] Forbidden to you (for food) are: dead meat, blood, the flesh of swine, and that on which hath been invoked the name of other than Allah; that which hath been killed by strangling, or by a violent blow, or by a headlong fall, or by being gored to death; that which hath been (partly) eaten by a wild animal; unless ye are able to slaughter it (in due form); that which is sacrificed on stone (altars); (forbidden) also is the division (of meat) by raffling with arrows: that is impiety. This day have those who reject faith given up all hope of your religion: yet fear them not but fear Me. THIS DAY HAVE I PERFECTED YOUR DEEN (ISLAM) FOR YOU. COMPLETED MY FAVOR UPON YOU, AND HAVE CHOSEN FOR YOU ISLAM AS YOUR DEEN. But if any is forced by hunger, with no inclination to transgression, Allah is indeed Oft-forgiving, Most Merciful.