The word εἰκών (from ἔοικα, ‘to seem, resemble') is translated ‘image,' and the words ὀμοίωσις and ὁμοίωμα (from ὅμοιος, ‘like') are translated 'likeness, similitude.'
In Gen. 1:26 both εἰκών and ὀμοίωσις occur in the LXX: "Let us make man in our image (εἰ.) and after our likeness (ὀμ)" In the N. T. these two words occur, in a similar use, with reference to man: he has this place in responsibility still: thus man "is the image (εὶ.) and glory of God" (1 Cor. 11:7.); and "men are made after the likeness (ὁμ.) of God." Jas. 3:9.
To be true to the image there must be moral likeness; but this involves for us a new creation. Hence (Col. 3:10): "the new man is renewed unto full knowledge after the image (εἰ.) of him that created him;" and Eph. 4:24 supplies the likeness (though the word is not used) "the new man which after God is created in righteousness and true holiness."
In Rom. 1:23 the words ὁμοίωμα and εἰκών both occur. It is said that men "changed the glory of the incorruptible God into the likeness (ὀμ.) of an image (εἰ) of corruptible man, and of birds," &c. Both words will also be found in reference to the Lord, He is the image (εἰ.) of God (2 Cor. 4:4; Col. 1:15); and He took a place "in the likeness (ὁμ.) of men" (Phi. 2:7); see also Rom. 8:3.
‘Similitude' in Heb. 7:15 is the rendering of another word ὁμοιότης, "after the similitude of Melchizedek."
For further remarks, see IMAGE in this Dictionary.