An example of this
Before I accepted Jesus as my Savior and became a Christian, I would get together with a bunch of my friends and we would play cards (poker) drink, swear, tell dirty jokes etc.
Now that I'm a Christian, I am not to be a part of this. How am I going to be a light to these lost souls if I partake of their sinful ways. That doesn't mean that we are to hide ourselves in a cave somewhere. We are in this world, we live and work amongst lost humanity but we are to be a light for Jesus to them.
2Corintians 6:14-16Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?
2Cor 6:15 And what concord hath Christ with Belial? or what part hath he that believeth with an infidel?
2Cor 6:16 And what agreement hath
the temple of God with idols? for ye are the temple of the living God;
as God hath said, I will dwell in them, and walk in them;
2Cor 6:17 Wherefore come out from
among them, and be ye separate, saith the
2Cor 6:18 And will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty.
Christians are in the world but we are not to be a part of it.
John 17:11-12And now I am no more in the world, but these are in the world, and I come to thee. Holy Father, keep through thine own name those whom thou hast given me, that they may be one, as we are.
John 17:12While I was with them in the world, I kept them in thy name: those that thou gavest me I have kept, and none of them is lost, but the son of perdition; that the Scripture might be fulfilled.
John 15:18-19If the world hate you, ye know that it hated me before it hated you.
John 15:19If ye were of the world, the world would love his own: but because ye are not of the world, but I have chosen you out of the world, therefore the world hateth you.
Christians are not to love this world.
1John 2:15-17Love not the world, neither the things that are in the world. If any man love the world, the love of the Father is not in him.
1John 2:16For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world.
1John 2:17And the world passeth away, and the lust thereof: but he that doeth the will of God abideth forever.
Notice that the devil offered Jesus the world.
Matthew 4:8-10Again, the devil taketh him up into an exceeding high mountain, and showeth him all the kingdoms of the world, and the glory of them;
Mat 4:9And saith unto him, All these things will I give thee, if thou wilt fall down and worship me.
Mat 4:10Then saith Jesus unto him, Get thee hence, Satan: for it is written, Thou shalt worship the Lord thy God, and him only shalt thou serve.
World - cosmos, The world in this case is the sphere of ungodliness that dominates mankind because of his fallen state. The word cosmos refers to order - arrangement and in the bad sense, the order - arrangement under which Satan has organized this world of fallen mankind upon his principles of selfishness, force, greed, ambitions, and pleasure. This world's system is very often outwardly religious, cultured, philosophical and refined, but blind to the truth.
If you make a stand for Jesus, don't expect the world to love you.
John 17:14I have given them thy word; and the world hath hated them, because they are not of the world, even as I am not of the world.
Remember this: As a child of God, you have a world wide family that loves you. There are many of us.
As we read and study and practice God's word it has a sanctifying effect on us.
Romans 12:1-2I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service.
Romans 12:2And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.
Read all of John chapter 17