Some consider the Lectures on Justification to be John Henry Newman's finest theological work. In "Lecture 9: Righteousness the Fruit of Our Lord's Resurrection," he wrestles with the difficult question of the mutual indwelling of Christ and the Spirit in the believer. He ends his lecture with reflections based upon the Book of Revelation:

I will conclude with directing attention to the vision of our Lord to St. John in the Book of Revelation, which also seems to me to be an intimation of the doctrine which I have been explaining. We know how our Lord appeared "in the days of His flesh;" in hunger and thirst, in weariness, in sorrow, in pain, in mortality. Such He is described in the Gospels, while His disciples saw Him; what His Presence is now, when they see Him not, we learn from St. John's vision. First He is said to be "in the midst of the Seven Candlesticks," or Churches; an expression which marks both that He is here and that His presence is spiritual. Then He is described, as follows:"His head and His hair were white as wool, as white as snow, and His eyes were as a flame of fire, and His feet were like unto fine brass, as if they burned in a furnace, and His voice as the sound of many waters. And He had in His right hand seven stars, and out of His mouth went a sharp two-edged sword, and His countenance was as the sun shineth in his strength." What words could be devised to express more forcibly the power and spirituality of His presence!Here then is certainly a representation of our Lord, the risen and glorified Saviour, living and ruling in His Church. Now it is very remarkable that, though He thus appears as Christ in the vision, yet in what follows He is spoken of as the Spirit, not as Christ, though He still speaks of Himself as Christ; as if to intimate that all the gifts His blood has purchased are ministered by the Spirit, and that what Christ was to His Apostles when on earth, such, and far more than such, is the Holy Ghost to us now. Here we seem to see something of the meaning of the words,"The Holy Ghost was not yet given, because that Jesus was not yet glorified;" for the gift brought by the Spirit was really this and nothing else: Jesus Himself glorified, ascended and invisibly returned.

The full lecture is here.