2 Corinthians 6:17-18
"Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing; and I will receive you, And will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty."
There are two important words for the Christian to understand.
The first word is "relationship," and the second word is "fellowship." A relationship is important because a person will never go to Heaven without having a relationship with Jesus Christ. You establish a relationship with Christ by accepting His payment on the cross for your sins. Jesus died, was buried and rose again so that He could establish a relationship with man. You will notice that having a relationship with Christ has nothing to do with man, but it has everything to do with God. All you have to do to establish a relationship with Christ is to put your whole faith and trust in Jesus Christ to be your Saviour, and at that moment you have a relationship established with Him.
Fellowship is completely different. You can have a relationship with Christ without having fellowship with Him. Fellowship is completely dependent upon how you live. For instance, my relationship with my parents was established because of them. It doesn't matter what I do, I will always be their son; likewise, once you are saved you will always have a relationship with Jesus Christ. However, my fellowship with my parents is dependent upon how well I obeyed them. If I was disobedient to my parents, then my fellowship was hindered and strained. If I obeyed them, then my fellowship with my parents was harmonious.
Our fellowship with God is dependent upon our separation. Notice in the verses above some key statements. God commands us to "come out from among them and be ye separate." Why are we to come out from the world? God shows us in verse 18 when He says, "And I will be a Father unto you, and ye shall be my sons and daughters,..." Notice, separation establishes the fellowship. If I don't come out and live a separated life from the world, then I cannot have fellowship with the Father. My fellowship with the Father is very dependent upon whether I live a separated life from the world.
You cannot separate by staying in the world. Too many Christians want to bring Christ into the world so they can have fellowship with Him, when He commands that we come out of the world to have fellowship with Him. Many churches today want to bring the world into their services, but they leave their fellowship with Christ by doing so. God will never change His principles with man just to have fellowship. It is a privilege to have fellowship with God, and that is why you must live a separated life from the world to have it.
Friend, don't let liberal preachers fool you into believing that it's okay to let down your standards. Those standards are there so that you can have fellowship with God. The greater your fellowship is, the better chance you have of getting your prayers answered. Separation has nothing to do with showing how great a Christian you are, but it has everything to do with whether you want to have fellowship with God. Separation is not a bad thing if you realize the results that it brings. Remember this, when you give up the world and separate from it, you get fellowship with God. Separation is a great thing if you look at it from that perspective. How is your fellowship with God? You show me how separated you are from the world, and I can show you your fellowship with God.