After a year of very slow reading, this afternoon I finished reading John Owen's Christologia: or, a Declaration of the Glorious Mystery of the Person of Christ in Volume 1 of his Works. This is not the same treatise as Meditations and Discourses on the Glory of Christ, which is also in this first volume (I'm still working on it). But it is well worth reading. Here are a few highlights that emphasize the necessity of faith in Christ for spiritual transformation and growth.
On 2 Cor. 3:18:
This glory which we behold, is the glory of the face of God in Jesus Christ, (chap. iv.6,) or the glorious representation which is made of him in the person of Christ . . . The glass wherein this glory is represented unto us - proposed unto our view and contemplation - is divine revelation in the Gospel. Herein we behold it, by faith alone. And those whose view is steadfast, who most abound in that contemplation by the exercise of faith, are thereby 'changed into the same image, from glory to glory' - or are more and more renewed and transformed into the likeness of God, so represented unto them. (p. 51)
In a chapter on the "spiritual efficacy of the divine image":
Wherefore, faith in Christ is the only means of the true knowledge of God; and the discoveries which are made of him and his excellencies thereby are those alone which are effectual to conform us unto his image and likeness. And this is the reason why some men are so little affected with the Gospel - not withstanding continual preaching of it unto them, and their outward profession of it. It doth not inwardly affect them, it produceth no blessed effects in them. Some sense they have of the power of God in the works of creation and providence, in his rule and government, and in the workings of natural conscience. Beyond these, they have no real sense of him. The reason is, because they have not faith - whereby alone the representation that is made of God in Christ, and declared in the Gospel, is made effectual unto the souls of men. (p. 77)
The same emphasis in a later chapter:
This faith in the person of Christ is the spring and fountain of our spiritual life. We live by the faith of the Son of God. In and by the actings hereof it is preserved, increased, and strengthened. "For he is our life," Col. iii.4; and all supplies of it are derived from him, by the actings of faith in him. We receive the forgiveness of sins, and an inheritance among them that are sanctified, "by the faith that is in him," Acts xxvi.18. Hereby do we abide in him; without which we can do nothing, John xv.5. Hereby is our peace with God maintained - "for he is our peace," Eph. ii.14; and in him we have peace, according to his promise, John xvi.33. All strength for the mortification of sin, for the conquest of temptation - all our increase and growth in grace - depend on the constant actings of this faith in him. (p. 132)