Is this passage about man being without excuse speaking about men who are spiritually alive?Theologians use the term Imago Dei to describe mankind being created in the image of God. In what way was mankind created Imago Dei? Mankind (Adam) was created with a mind capable of rational thought. This is different than all other living creatures God created. Mankind was created in a state of innocence. He had no culpability or familiarity with sin. In this regard, he was created in the moral likeness of the triune God. Adam was created with both a physical body and an immaterial spirit. It is the immaterial part of man that is made in God's image. It is the immaterial part of man that has an intuitive morality. It cannot be the flesh that is made in God's image because God is spirit. Even the Son of God had not been manifest in human form during the creation event.
No other passage of scripture emphasizes the moral nature of the Imago Dei more clearly than Romans 1:18-20:
"For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men who suppress the truth in unrighteousness, because that which is known about God is evident within them; for God made it evident to them. For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse." (emphasis mine)
The only way mankind can be without excuse is to possess the moral capacity to know right from wrong. Adam has this capacity when he was created. Ergo, the moral nature of the Imago Dei is beyond refutation.