He that walketh with wise men shall be wise: but a companion of fools shall be destroyed. (proverb 13:20)

This proverb has a lot of meaning to it. It is telling you what is one of the things you must do to be good. If you want to be wise and good then you must not follow bad influences. If you have a companion that is a fool and makes foolish decisions then you will by nature follow his or her foolish decisions. That is why if you walk with a band of wise men you shall be wise as well. In order to be the best that you can be and not make foolish decisions you must hang out with the right crowd, the good crowd.