10. the new man--(See on Eph 4:23). Here (neon) the Greek, means "the recently-put-on nature"; that lately received at regeneration (see on Eph 4:23, 24).
      which is renewed--Greek, "which is being renewed" (anakainottmenou); namely, its development into a perfectly renewed nature is continually progressing to completion.
      in knowledge--rather as the Greek, "unto perfect knowledge" (see on Col 1:6; Col 1:9, 10). Perfect knowledge of God excludes all sin (Joh 17:3).
      after the image of him that created him--namely, of God that created the new man (Eph 2:10; 4:24). The new creation is analogous to the first creation (2Co 4:6). As man was then made in the image of God naturally, so now spiritually. But the image of God formed in us by the Spirit of God, is as much more glorious than that borne by Adam, as the Second Man, the Lord from heaven, is more glorious than the first man. Ge 1:26, "Let us make man in our image, after our likeness." The "image" is claimed for man, 1Co 11:7; the "likeness," Jas 3:9. ORIGEN [On First Principles, 3:6] taught, the image was something in which all were created, and which continued to man after the fall (Ge 9:6). The likeness was something towards which man was created, that he might strive after it and attain it. TRENCH thinks God in the double statement (Ge 1:26), contemplates both man's first creation and his being "renewed in knowledge after the image of Him that created Him."

JFB.