How are believers one with Christ using the marriage analogy?
The marriage analogy illustrates that just as husband and wife become one, believers and Christ are one. Therefore, if anyone is in Christ, he is a new man. This oneness is not produced by fixing up the old; it is a new creation when God's outside power energizes the dead spirit.
Les teaches that the marriage analogy means that as husband and wife become one, so you and I and Christ are one. From that union, if any man be in Christ, he is a new man. Les explains that you cannot just fix up the old; the old is like a dead battery that may be cleaned until it shines, but it remains dead and has no power. Adam's sin made his soul a sin nature, killed the spirit, and broke fellowship with the Creator. Spiritually, we have been dead as a result of Adam's sin, and it takes an outside source of power—the power of God—to energize our spirit. When He energizes the spirit, He makes us a new person, or a new creation.