The believer is not immune from the temptation to sin but the grace  of God which is at work in him allows him to say no to sin (Titus 2:11).  The saint has come into a new life in which the natural appetites and  desire to sin have been subdued and now he is alive unto righteousness.

If you have not come to this point in your life where you no longer  have a raging desire for sin, then it is likely you are still in your  old life.

The Bible says that if any man is in Christ, he becomes a new  creature, he gets a new life, a new desire, a new way to live, and old  things are passed away and behold he is a new man living a new life in  His living Saviour (2 Corinthians 5:17).

Even when in reality you have come into the life in Christ, you are  not exempted from temptations to go back to your old life of sin. The  tempter i.e. the devil does not want to lose any soul and will do  anything to bring a saved soul back into his net. He tempts the believer  with all manner of sin, to sever the saint from being connected to God.