I read this part: "Do not stoop to hurling an insult back."

As this: "Do not stop hurling insults back."

Be clear and direct with your response. Do not stoop to hurling an insult back. Defend yourself if there’s anything to defend, own up to any mistakes if there are any to own up to, and make it clear you do not tolerate being spoken to with derision

Clearly written by a jew, we reserve the right to insult and berate you, but dont you dare fight back or do anything you stupid goy!