One Piece Chapter 6, page 5: Chapter 6: Number One

Zoro addresses Luffy while keeping his swords ready, saying, "ALL RIGHT, SO I'M A PIRATE. I GAVE YOU MY WORD. I'VE FOUGHT THE NAVY, THEREFORE I'M OFFICIALLY AN OUTLAW... BUT, HEAR THIS!! I HAVE A MISSION TO FULFILL!!!" He looks directly at Luffy with fierce determination and declares, "I'M GOING TO BE THE WORLD'S GREATEST SWORDSMAN! ALL I HAVE LEFT IS MY DESTINY! MY NAME MAY BE INFAMOUS... BUT IT'S GONNA SHAKE THE WORLD!!!" He then adds a stern warning: "BUT YOU ARE MAKING ME BECOME A PIRATE! SO IF I HAVE TO ABANDON MY DREAM FOR ANY REASON......THEN I'M GOING TO MAKE YOU COMMIT HARA KIRI!!!"