I. The Definition, Seat, and Multi-faceted Nature of the Image
"The image of God in man, is a mind rightly knowing the nature, will, and works of God; a will freely obeying God; and a correspondence of all the inclinations, desires, and actions, with the divine will; in a word, it is the spiritual and immortal nature of the soul, and the purity and integrity of the whole man; a perfect blessedness and joy, together with the dignity and majesty of man, in which he excels and rules over all other creatures." [Zacharias Ursinus - Commentary on the Heidelberg]
"For though the divine glory is displayed in man's outward appearance, it cannot be doubted that the proper seat of the image is in the soul." [John Calvin - Institutes]
"The essence of man lies in this, that he is God’s image." [Herman Bavinck - Reformed Dogmatics]
"The Bible says that man — not merely the soul of man — was created in the image of God, and man, the 'living soul,' is not complete without the body." "We need not look for the image in the material substance of the body; it is found rather in the body as the fit instrument for the self-expression of the soul." [Louis Berkhof - Systematic Theology]
"And though the primary seat of the divine image was in the mind and the heart, or in the soul and its powers, there was no part even of the body in which some rays of glory did not shine." [John Calvin - Institutes]
II. Original Righteousness (Knowledge, Righteousness, and Holiness)
"The image of God in man at the first doth include the universal and perfect rectitude of the whole soul: knowledge in his understanding, righteousness in his will, holiness in his affections." [Thomas Vincent - The Shorter Catechism]
"The New Testament indicates very specifically the nature of man’s original condition where it speaks of man as being renewed in Christ, that is, as being brought back to a former condition. The condition to which he is restored in Christ is clearly not one of neutrality, neither good nor bad, in which the will is in a state of perfect equilibrium, but one of true knowledge, Col. 3:10, righteousness and holiness, Eph. 4:24." [Louis Berkhof - Systematic Theology]
"Positively, the image of God doth consist in the inward resemblance of his soul to God, in knowledge, righteousness, and holiness." [Thomas Vincent - The Shorter Catechism]
III. The Vitiation and Loss of the Image Through the Fall
"But after the fall, man lost this glorious image of God, on account of sin, and became transformed into the hateful image of satan." [Zacharias Ursinus - Commentary on the Heidelberg]
"Wherefore, although we grant that the image of God was not utterly effaced and destroyed in him, it was, however, so corrupted, that any thing which remains is fearful deformity; and, therefore, our deliverance begins with that renovation which we obtain from Christ, who is, therefore, called the second Adam, because he restores us to true and substantial integrity." [John Calvin - Institutes]
"But those things which we have lost of the image of God are by far the greatest and most important benefits; of which we may mention the following: 1. The true, perfect, and saving knowledge of God, and of the divine will. 2. Correct views of the works of God, together with light and knowledge in the understanding; in the place of which we now have ignorance, blindness, and darkness. 3. The regulation and government of all the inclinations, desires, and actions; and a conformity with the law of God in the will, heart, and external parts; instead of which there is now a dreadful disorder and depravity of the inclinations and motions of the heart and will, from which all actual sin proceeds."
IV. The Remains and Sparks of the Image in Fallen Man
"There were, however, some remains and sparks of the image of God still left in man, after his fall, and which even yet continue in those who are unregenerated, of which we may mention the following: 1. The incorporeal, rational, and immortal substance of the soul, together with its powers, of which we would merely make mention of the liberty of the will, so that whatever man wills, he wills freely 2. There are, in the understanding, many notions and conceptions of God, of nature, and of, the distinction which exists between things proper and improper, which constitute the principles of the arts and sciences. 3. There are some traces and remains of moral virtues, and some ability of regulating the external deportment of the life. 4. The enjoyment of many temporal blessings. 5. A certain dominion over other creatures." [Zacharias Ursinus - Commentary on the Heidelberg]
"But the image of God is not to be restricted to the original knowledge, righteousness, and holiness which was lost by sin, but also includes elements which belong to the natural constitution of man. They are elements which belong to man as man, such as intellectual power, natural affections, and moral freedom." [Louis Berkhof - Systematic Theology]
"Still, in this diversity we can trace some remains of the divine image distinguishing the whole human race from other creatures." [John Calvin - Institutes]
V. The Divine Restoration of the Image in Jesus Christ
"The restoration of this image of God in man, is effected by him alone, who first conferred it upon man; for he who gives life, and restores it when lost, is the same being." "God the Father, restores this image through the Son; because he has 'made him unto us wisdom, righteousness, sanctification, and redemption.' (1 Cor. 1:30.) The Son, through the Holy Spirit, 'changes us into the same image, from glory unto glory, as by the Spirit of the Lord.' (2 Cor. 3:18.)" [Zacharias Ursinus - Commentary on the Heidelberg]
"Accordingly through the blessing of Christ we are renewed by that regeneration into the righteousness of God from which we had fallen through Adam, the Lord being pleased in this manner to restore the integrity of all whom he appoints to the inheritance of life." [John Calvin - Institutes]