I told him to stop bothering my friend. He was threatening to hack his IP. What's wrong with telling him to leave him alone.
If people harass your friend you shouldn't just join a server with that person just to flip stuff. you seem to do this a lot.
You could have just taunted him a little and said "Hack me, come on, I'm waiting" And let him get over his anger with the fact that he cannot do stuff to you, then leave. I mean, did your friend believe this person? If so, you could have explained to him that hacking is impossible in blockland unless you take advantage of some coding inside a mod everyone has, which is not necessarily hacking. And it's pretty immature to jump into a server and start cussing at him anyway. You should have just told your friend that he could not be hacked in the game and left him alone. You need to stop taking this stuff so seriously, and so does he.