The Bible teaches clearly that the evidence of God’s work in a life is the inevitable fruit of transformed behavior (1 John 3:10). Faith that does not result in righteous living is dead and cannot save (James 2:14-17). Professing Christians utterly lacking the fruit of true righteousness will find no biblical basis for assurance they are saved (1 John 2:4). Real salvation is not only justification. It cannot be isolated from regeneration, sanctification, and ultimately glorification. Salvation is an ongoing process as much as it is a past event. It is the work of God through which we are “conformed to the image of His Son” (Romans 8:29, cf. Romans 13:11). Genuine assurance comes from seeing the Holy Spirit’s transforming work in one’s life, not from clinging to the memory of some experience.
John MacArthur