What is the new man according to Ephesians 4?
The new man in Ephesians 4 is the new creation believers put on, in contrast to the old man, the old Adam. It is created after God—by the Holy Spirit's power—in righteousness and true holiness. When God moves in, this new created part replaces the old corrupt manner of living and enables renewed living.
Les explains that Ephesians 4:22-24 tells believers to put off the former manner of living, the old man, that old Adam, which is corrupt according to deceitful lusts or desires. Then they are to be renewed in the spirit of their mind and put on the new man, not the old Adam. The new man is after God—after God moves in, in the power of the Holy Spirit—so that we have a creation, a new created part of us, created in righteousness and true holiness. Les also connects this to Romans, where since the old Adam is dead, we do not have to let him rule and reign in our lives; we reckon him dead. When this happens, Paul can instruct us about the change in our living, putting aside the things that were before commonplace and natural.
And that ye put on the new man, which after God is created in righteousness and true holiness.