I regret to inform you that your appeal has been officially denied.
You have threatened a staffer, and admitted so yourself in the post to which I am replying, stating that you would use potion effects to "disable" them. Unfortunately this would fall under both non-consentual PvP and Ruining the Experience of others. It should be noted that neither of these actions are permitted.
I apologize for the lack of enforcement on previous iterations of the server. Moving forward bugs and glitches that may be used and exploited to gain unfair advantages will be investigated and handled appropriately. The rule that would apply to said situation would be covered under exploits.
Respect is earned, I would agree. However in the process of earning respect one must also treat others with it. Threatening staff as well as the server are not respectful. Neither would be petty name calling or cruel jokes. It should be noted that proof of how certain staff feel about you have no relevance to the situation. Staff treat all players equally regardless of personal feelings.
Threats come in many forms. In your case when you believed staff would take action against you that you disagreed with, you stated in a vague threat that you could "break the server." This constitutes a threat.
I agree that putting that as a reason is unprofessional, and concede that it was not appropriate. That being said, given your previous actions I would not expect an apology. I would also note that you asked him to apologize for his "harsh language and opinion about me." One should not be expected to apologize for a personal opinion.
In conclusion you will not be receiving a second chance. We understand the server may be important and you wish to play with friends, but such behavior can not be allowed to continue.