AinOhdMilvado: Wearing arba kanfos without tzitzis is being mevatel an aseh. Not wearing arba kanfos is simply not being mechuyav. Similarly, if you don’t own chometz on erev pesach you are not being mivatel tashbisu.
Bezalel: It’s in the mishepara in perek Hazahav in bava metzia. It refers to someone who sells indigo and claims it’s tcheles. In context, it’s a curse on someone who passes off counterfeit merchandise dishonestly. Scary stuff. IIRC the nusach includes the Egyptians, the prophets of Baal who challenged Eliyahu and lots of other very miraculously, very dead sinners.