We all, with unveiled face, beholding as in a mirror the glory of the Lord, are being transformed into the same image from glory to glory. (2 Corinthians 3:18)
The word 'beholding' is a strong word; it is not just taking a look, it is 'fixing our gaze.' That is what the New Testament means by beholding, behold. We all, fixing our gaze upon Christ, as He mirrors in His own Person the glory of God, the satisfaction of God, the mind of God in perfection. The point is that you and I must contemplate the Lord Jesus in spirit, and be much occupied with Him. We must have our Holy of Holies where we retire with Him. We must have a secret place where we spend time with Him. And not only in certain special seasons, but we must seek, as we move about, ever to keep Him before us. Looking at the Lord Jesus, contemplating Him, we shall be changed into the same image. The Holy Spirit will operate upon our occupation.
You become like that which obsesses you, which occupies you. Is that not true? You see what people are occupied with, and you can see their character changing by their obsessions. They are becoming like the thing which is obsessing them; they are changing; they are becoming different. Something has got a grip on them; they can never think about anything else, talk about anything else; and it is changing their character. Now Paul said, "For me to live is Christ – being occupied with Him." It is the wrong word to use, but nevertheless it would be a good thing if He became our "obsession," our continuous occupation. As we steadfastly fix our gaze upon Him, the Spirit changes us into the same image.
By T. Austin-Sparks from: Men Whose Eyes Have Seen The King - Chapter 4