According to how I was taught it by the Jehovah's Witnesses it means being friends with the world will spoil a person's relationship with God.
If that be so then, is a person's relationship with God a "useful habit"?
How do you understand that scripture, and please also comment on what "bad associations" means to you.
This is how I read it in the Greek interlinear
corrupts
character
good
companions
bad
1 Corinthians 15:33 Greek Texts and Analysis
Savagewind,
Another scripture that goes along with this principle is at Prov 13:20. Everyone knows that a person that associates with another, often, will pick up some of their idiosyncracies.
The Bible tells us what the things of the flesh are, and what the things of the spirit are, Gal 5:19-23. Rom 8:4-8 explains how the thing of the flesh and the things of the spirit affect us. It seems that here we are told that it we are minding the flesh, we are sure to die, but if we are minding the spirit we gain everlasting life.
Another point to think about, is what Jesus said to Pontius Pilate at John 18:36. Jesus said that his Kingdom is no part of this world. James 4:4 says that a person who loves this world is an enemy, 1John 2:15-17. These things of the world, trying to gain riches, trying to gain power, politics, the military, gambling, showy display of ones means of life are all things of the world. All these things are a distraction to a Christian who wants to keep his mind on the coming kingdom, and the spiritual things, Matt 6:19-24, 31-33.
A Christian must be a footstep follower of Jesus, 1Pet 2:21, a person who has his interest on the things of this world cannot help a Christian to keep strong in his faith.
This probable why Paul wrote what he did at 2Cor 6:14-18.
In this wicked world it is very hard to keep ones mind on the things of the spirit when we are constantly bombarded with immorality at every turn, movies, books, even commercials, the internet, tv games. Having too much association with a person who has his mind on these things will not help a Christian to be strong in resisting these things, 1Pet 5:8-10, Eph 6:10-13.
A very real problem is that many people pretend to be Christians and are not, Titus 1:16, 1John 2:6, 3:18, Matt 7:21-23, 2Cor 11:12-15.