The person who is not born again and or saved by grace knows nothing of the constant struggle between the new nature and the old nature. The one who does not know Jesus as Lord has no understanding of two opposite powers seeking mastery over their life. The reason for this is that this person only has one nature, the sinful nature. Born in sin, they choose to live in sin; it is a natural way of life. If a person becomes born again and is again entangle in loose living and lives carelessly, this old nature has the power to overcome them, even to the point of losing their salvation.
If a sheep and a pig are turned loosed into a pasture where there is a dirty mud hole and a beautiful grassy hill, where will each animal go and why? If the sheep should come too close to the mud hole, which the pig is content, and falls in, it would immediately cry out for the shepherd, revealing its awareness that it is in an environment foreign to its nature. The sign of the believer in Christ Jesus is the hatred for the mud of sin lest the new nature be defiled. Believers are never immune from falling into the pig’s hole of sin, for the soul is ever a battlefield in which opposing forces of sin and holiness are in conflict. The believer comes to the knowledge that their soul is forever seeking to escape the corruption that is in the world through lust. Through God’s grace and the Holy Spirit’s power alone we will not return to sin like a sow that was washed returning to her wallowing in the mire, 2 Peter 2:20-22. Peter so rightly states, that if we are again entangled in the defilement’s of the world after experiencing Jesus’ saving grace, that condition and place are worse for them than the first. Peter goes on to say through the Holy Spirit, it would have been better that they never experienced salvation through God’s grace in Christ Jesus.
That sweet tender voice of the Holy Spirit is always saying to us, come upward; ascend to the heights of the upward call of God. We are to come up to the realm where the air is pure. Yet, there is another voice which comes through the sinful nature that is always saying, come downward to the lowliness of sin, rebellion, and possession. This voice is looking to conquer, dominate, and control our daily life. My question to us is, which voice are we going to give place too? Jesus heard this same voice on the cross, delighting in doing the will of God and His highest calling, in His agony heard, come down from this place of shame and we will believe you.
Again the choice will always be ours. Paul felt the carnal dragging himself down in Romans 7, and although he was a child of God he knew that in him there was no good thing. The new man will always be in conflict with the old man, who are we going to obey?