Am I a true Christian, or am I a counterfeit?

How To Examine Yourself

Examine yourselves to see whether you are in the faith; test yourselves. Do you not realize that Christ Jesus is in you—unless, of course, you fail the test? (2 Corinthians 13:5).
When we are out of line with Christian standards we have to ask ourselves, "Am I a true Christian, or am I a counterfeit? Have I been born again, or am I only putting up a front?" Those of us who are Christians ought to ask ourselves that occasionally. It is a good idea to examine yourself, especially if there is any kind of wrong behavior involved.
The very fact that the apostle could ask a question like that indicates that a possible answer is what marks true Christianity. A Christian, of course, is not simply one who joins a Christian church. Nor does adhering to a certain moral standard in your life or the fact that you consistently read the Bible make you a Christian. A true Christian is someone in whom Christ dwells. And the person in whom Christ dwells will have certain inescapable evidence of that fact given to him or her. Paul is suggesting that we ask ourselves if we have the evidence that Jesus Christ lives in us.
You may be asking, "How can I know that?" The answer is found in several places in Scripture. For instance, Scripture speaks of an "inner" witness. In Romans Paul says, "The Spirit himself testifies with our spirit that we are God's children" (Romans 8:16). That is one way you can know. There is an inner testimony, a feeling, a sense within produced by the Spirit of God who dwells within that you are part of the great family of God.
Scripture speaks also of desires that are born in the heart of a new Christian. First Peter 2:2 says, "Like newborn babies, crave pure spiritual milk, so that by it you may grow up in your salvation." One of the marks of born-again believers is that they have a deep and sudden thirst for the Word of God, a hunger to be fed, to know the truth of God.
This inner change will also produce an outward change, which is not all subjective. We can answer the question, "Is Jesus Christ in you?" by observing our conduct, because the inner change will produce a different attitude toward our behavior. One of the striking things about new Christians is that they invariably begin to manifest a totally different attitude toward things they once thought were appropriate. In some of the more blatant forms of evil, such as attitudes about lying or drunkenness or stealing, they find immediately that their attitude is changed. That is because Christ lives in them, and light can have no part with darkness. Christ cannot share with Belial. Even our attitude toward our selfishness changes. We see how selfish we have been. It looks ugly and distasteful in our eyes, and we want to be free from it.
From the book The Power of His Presence: a year of devotions from the writings of Ray Stedman
http://www.raystedman.org/power/0929.html

YOU CAN KNOW YOU ARE SAVED

The Holy Bible tells us we can know we are saved. 1 John 5:13 states I have written these things to you who believe in the name of the Son of God so that you may know that you have eternal life.

The Bible also tells us in 2 Corinthians 13:5 Test yourselves to see if you are in the faith; examine yourselves! Or do you not recognize this about yourselves, that Jesus Christ is in you--unless indeed you fail the test?
So how is it that a person may know they are saved?
We are to examine ourselves to see (1) whether we are in the Christian faith and (2) whether or not Jesus Christ dwells in us by His Spirit.

If we have been born again, have believed by faith and repented then our lives will give evidence of the fact that we are saved. When we become saved God changes us from the inside out. Noticeable changes are the inevitable result. God gives the believer new desires and a new way of thinking. Those are just two examples of changes which become noticeable in a Christian. 2 Corinthians 5:17 says; Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.

The one verse of Scripture which ties this all together is ........
Romans 8:16 The Spirit itself beareth witness with our spirit, that we are the children of God:
God gives those who are saved an internal witness. He witnesses to our human spirit by His Spirit that we are saved. This internal witness by God's Holy Spirit is an unmistakable witness which God gives to every born again believer.

So if you have examined yourself, have believed and have become born again, as well as experienced evident changes in your life, and have God's Spirit internally witnessing with your human spirit, then you can rest assured that you are saved.

Becoming Born Again Is Entirely A Work Of God

"If salvation is the implantation of a new, infinite life in the soul, it must be a work of God. Self-caused effects can never rise above the character or qualities of their cause. "Flesh gives birth to flesh but the Spirit gives birth to Spirit," Jesus told Nicodemus. This saving grace cannot be caused by the creature, it can only come from God." - John Hannah from To God be the Glory (pg. 34-5)

The new birth comes by sovereign action.

"I remember that sacred time when the Spirit regenerated me, though I understood nothing of the theology of it. One day my mind was dark to the gospel and things of God; the next, it was as though a floodlight came on and I saw what I'd never been able to see and understood what had always been a fog to me. My desires the day before were wholly self-centered; the next day, my heart melted at the things of God and inclined toward Christ. The way that I looked at everything changed from that moment. I believed the gospel; I put my trust in Christ; I committed myself to be His follower. But none of this happened until the Holy Spirit turned on the lights in my darkened mind and soul. I did not even understand enough before this to ask the Lord to regenerate me! He just did it; then I believed the gospel. That's why the use of the passive voice in "born again" is critical for us to grasp? The new birth comes by sovereign action." - http://www.southwoodsbc.org/sermons/john_03.01-08.html