Man does not change in order to be saved, but true salvation always brings about an evident change in the life of the new believer. Perhaps the change is less noticeable in some new believers and more noticeable in others; however, no change means no salvation. The change is not always an immediate outward change because it involves a change of the inward nature. A person who trusts Christ for salvation becomes a new creature (Galatians 6:15). It might be best to consider how this could be likened to a dog (Matthew 15:26-27) becoming a sheep (John 10:16). A new man now dwells within the new Christian to help combat and defeat the old sinful nature (Ephesians 4:22-24). Salvation is not merely the turning over of a new leaf; it is a new birth (John 3:3) where one is passed from spiritual death to spiritual life (John 5:24).
God wants everyone to be firmly established in sound doctrine. The more time an individual spends in his Bible, the better grounded in truth he becomes. With the importance placed upon establishing believers, God warned about being “carried about with divers and strange doctrines” (Hebrews 13:9) and about being “tossed to and fro, and carried about with every wind of doctrine” (Ephesians 4:14). The Devil hates Christians who become rooted and grounded in the truth. This is why he weakens and destroys believers by propagating doctrines contrary to scripture. Men may be the facilitators of false doctrines but the ultimate plan of deception is crafted by the Devil himself.