You can enter passive mode by using the command :passive This can only be done inside a safezone while you are out of combat and not aggressive. Switching to passive mode takes 15 seconds.
You can see if someone is in passive mode by the green enable above their head, and the Passive tag by their target.
While in passive mode you will not be able to do the following:
Everything else is still usable and doable in passive mode. This includes criminal activities, heists and farming.