He who walks with wise men will be wise,
but a companion of fools will be destroyed.
This world is filled with influences. They are all around us, all the time. Some influences are good, and some are evil. If you welcome good influences and resist evil influences, you are wise, but if you welcome evil influences and resist good ones, you are foolish.
No one in this world can escape being influenced. It is an inescapable fact of life. The only issue is, Are we wise in our choice of influences, or are we foolish?