"Be not deceived: evil communications corrupt good manners." 1 Corinthians 15:33
In the Greek, "communications" is companionship or intercourse. Think about this in this context. The company we keep will influence us either for good or bad!
If you had to choose between 2 strawberries to eat, one is freshly picked, bright, sweet smelling and the other is brownish grey, foul smelling, smooshy and molded. Which would you choose to satisfy your taste buds. More than likely the fresh one, right?
We are to be picky about those we surround ourselves with too! If that rotten strawberry, described above is left with the fresh fruit; it's spoiled juices will rot the whole container!
In the same manner, so will bad company or "evil communications"!
Jesus said, "Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles? Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. A good tree cannot bring forth evil fruit, neither [can] a corrupt tree bring forth good fruit. Every tree that bringeth not forth good fruit is hewn down, and cast into the fire. Wherefore by their fruits ye shall know them." Matthew 7:16-20
In essence, be wise in your choosing. Be a fruit inspector! There's a major difference in witnessing to the lost, broken, blinded & corrupted people verses choosing to indulge in their lifestyles.
Remember, if you're in Christ, we are IN this world but NOT of it! Be careful with the company you keep. It's rewards or consequences could be detrimental to the soul!