Not only do insults have absolutely zero possibility to do physical or psychological harm to you, but the same thing goes for anything someone says to you.
If someone expresses their disappointment in you, orders you to do something, tells you did something wrong or stupidly, those words have as much ability to physically or emotionally hurt you as if someone had told you: ‘Sdnuiqzxc asdhuqwd zxcbnbnsa zxb bxb, oqwu bnaciu bsa uiqwye iqwu. Avbullqqmnc asdh hyq wyqy ww hhvvqitsds qp!!!’
Words are nothing but a series of letters arranged in a certain order to make a certain sound that comes out of the face hole.
A very small percentage of people actually say things to purposelly piss you off. But even then, it’s your interpretation of it that makes you pissed off.
Pretty much 99% of the people in the world are trying to get along in the world (and with others) to make their lives better. But, the problem is our expectations are on the opposite end of that scale. Our purpose for life might match up, but our expectations rarely do. And that’s the only reason people say things or do them in ways you don’t like or understand.
And anyway, if someone says something shitty about you, everything is constantly changing, and just because they said it, one, it does not make it true, but two, it’s a chance to show yourself how strong and balanced you are, and three, the next split second (if you agree with them) is a chance to turn your behaviour around.
It’s about focusing on what you can control and forgetting what you can’t.
You have 0 control over what others say but you have 100% control over how you see it. And that’s what the Stoics taught.
If you face everything with calmness and indifference, nothing can hurt you. You know, except for actual physical things, like getting shot by a cannon or boxed on the ears (and even then…)