If the flesh is the image of the first man (Adam), in what sense are Christians in the image of the second man (Christ)?

In passages such as First Epistle to the Corinthians 15:45–49, Paul the Apostle contrasts the first man, Adam, with the second man, Christ: >“The first man Adam became a living being; the last Adam became a life-giving spirit… Just as we have borne the image of the man of dust, we shall also bear the image of the man of heaven.”
(1 Cor 15:45–49) This seems to suggest that humanity bears the image of Adam in a physical or natural sense (“man of dust”). My question is: In what sense do Christians bear the image of the second man, Christ? - Is this image spiritual (e.g., regeneration, righteousness, new nature)? - Is it future, referring primarily to the resurrection body?