Repenting is an action (work) that the born again child of God does because he is pricked in his heart of breaking a spiritual law. The work of repenting is not the cause of your eternal salvation, but an action that you are already born of the Holy Spirit. The natural man, void of the indwelling of the Holy Spirit will not feel guilty of breaking a spiritual law that he cannot discern and will never repent of something he does not understand.(1 Cor 2:14). James 1:15 - Then when lust hath conceived, it bringeth forth sin: and sin, when it is finished bringeth forth death (separation) from the fellowship with God, not separation from eternal life). The natural man, until he has been given the Holy Spirit in regeneration, cannot be pricked in his heart because he has not yet been born again and given a new heart.