He that walketh with wise men shall be wise: but a companion of fools shall be destroyed.

Proverbs 13:20

I think this means if the people you hang out with are CTR people then they won't let you do anything that is wrong. A group of bad people to hang out with will get you in trouble. Those bad people will pressure into doing things that are bad and you wouldn't do normally.

Hanging out with people can change how you are as a person. It is important to hang out with the good people so you can be a good person.