"For the natural man is an enemy to God, and has been from the fall of Adam, and will be, forever and ever, unless he yields to the enticings of the Holy Spirit, and putteth off the natural man and becometh a saint through the atonement of Christ the Lord, and becometh as a child, submissive, meek, humble, patient, full of love, willing to submit to all things which the Lord seeth fit to inflict upon him, even as a child doth submit to his father."
The natural man is an enemy to God, and part of who we are. Part of who we are is also spiritual, so, in essence, we are fighting with ourselves in large measure while we are on this earth. I think we feel that sometimes... two large parts of ourselves internally at war. I think that the "and will be, forever and ever" line tells us exactly what our eternity will be like, unless we learn to submit to the Lord's will, and teach our whole selves to work together. How do we do that? It tells us that here as well. We have to learn to be submissive. To put God's will before our own. We have to remember that we are the children of God, and that we need to learn from him how to grow up to be like him. We can't learn from him very well if we are allowing ourselves to be his enemy. ... It's a huge challenge to have two warring parts of ourselves, but one that God helps us with as we look to him and desire his help. As we strive to keep the spirit with us, we'll learn more and more how to be whole, and to allow the spiritual to care for and guide the physical.