Sounds to me he's looking to get a rise from you.
Reputation is what other people know about you. Honor is what you know about yourself.
Don't stoop to his level. If you perhaps are slightly responsible for what he's doing (only you know this for sure), try to learn from it & don't repeat past mistakes.
If it gets too bad, I would make a police report or move business location. But avoid contact w/this person, it will not help.
Second thoughts can generally be amended with judicious action; injudicious actions can seldom be recovered with second thoughts.
--Cyteen by C.J.Cherryh