Ingolf Dalferth, Creatures of Possibility: The Theological Basis of Human Freedom (2016), 12–14:
From time immemorial, this representation of the human person has been taken theologically as an interpretation of the biblical reference to the human being as imago Dei (the image of God). Humans are related to God in that they are endowed with reason, but they manifest their likeness to God as in a mirror obscurely, because they are animals and not (only) reason, as God is.
This interpretation of the doctrine of human beings created in the image of God, which took as its reference point the image of human beings as animals endowed with reason, had disastrous consequences for the interpretation of human creatureliness and sin.
The creation-theological distinction between God and humankind became associated in a confusing way with the hamartiological distinction between true humanity as intended by God and fallen humanity as it actually is; the human faculty of reason was linked with human God-relatedness, whereas the human animal nature was linked with the human state of separation from God. Thus the problem of sin was read into the animal nature of humankind, with the far-reaching consequence that every animal and physical impulse was suspected of separating and turning human beings away from their Creator.
Conversely, relationship with God became focused entirely on reason, with the equally far-reaching consequence that reason became the definitive touchstone for determining whether it was possible to treat God seriously as God and the human person seriously (or even at all) as God’s creation. . . .
This singles human beings out, but it also puts them in a permanently precarious position. Neither mere animals nor wholly angels, they are compelled to find their identity on the border between two orientation points, neither of which they can lose sight of, lest they fall headlong and fail to achieve their potential. For whenever they want to be more than they are, behaving as if they were angels, they in fact become less than they are: inhuman animals. And whenever they want to be less — in other words, mere animals — they do not even achieve the level of animal life.