For if any be ... - The ground of the comparison in these verses is obvious. The apostle refers to what all persons experience, the fact that we do not retain a distinct impression of ourselves after we have looked in a mirror. While actually looking in the mirror, we see all our features, and can trace them distinctly; when we turn away, the image and the impression both vanish. When looking in the mirror, we can see all the defects and blemishes of our person; if there is a scar, a deformity, a feature of ugliness, it is distinctly before the mind; but when we turn away, that is “out of sight and out of mind.” When unseen it gives no uneasiness, and, even if capable of correction, we take no pains to remove it. So when we hear the word of God. It is like a mirror held up before us. In the perfect precepts of the law, and the perfect requirements of the gospel, we see our own short-comings and defects, and perhaps think that we will correct them. But we turn away immediately, and forget it all. If, however, we were doers of the word,” we should endeavor to remove all those defects and blemishes in our moral character, and to bring our whole souls into conformity with what the law and the gospel require. The phrase “natural face” (Greek: face of birth), means, the face or appearance which we have in virtue of our natural birth. The word glass here means mirror. Glass was not commonly used for mirrors among the ancients, but they were made of polished plates of metal. See the Isaiah 3:24 note, and Job 37:18 note.
For he beholdeth himself - While he looks in the mirror he sees his true appearance.
And goeth his way, and straightway forgetteth - As soon as he goes away, he forgets it. The apostle does not refer to any intention on his part, but to what is known to occur as a matter of fact.
What manner of than he was - How he looked; and especially if there was anything in his appearance that required correction.