Was known to the Egyptians at a very early period of their national history, at least B.C. 1500. Various articles both useful and ornamental were made of it, as bottles, vases, etc. A glass bottle with the name of Sargon on it was found among the ruins of the north-west palace of Nimroud. The Hebrew word zekukith (Job 28:17), rendered in the Authorized Version “crystal,” is rightly rendered in the Revised Version “glass.” This is the only allusion to glass found in the Old Testament. It is referred to in the New Testament in Rev. 4:6; 15:2; 21:18, 21. In Job 37:18, the word rendered “looking-glass” is in the Revised Version properly rendered “mirror,” formed, i.e., of some metal. (Comp. Ex. 38:8: “looking-glasses” are brazen mirrors, R.V.). A mirror is referred to also in James 1:23.
Glass
A glass in the King James Bible is a mirror, and it shows up in three useful pictures. Paul writes, “For now we see through a glass, darkly; but then face to face,” admitting that what we know now is partial. In 2 Corinthians 3:18 believers behold the glory of the Lord in a glass and are changed. James has a plainer use: a hearer of the word who does not act is like a man who looks at his face, goes away, and forgets what he looked like. A mirror shows what is there, and it only helps if the person then does something.
4 verses
1 Corinthians
For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.
2 Corinthians
But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord.
James
For if any be a hearer of the word, and not a doer, he is like unto a man beholding his natural face in a glass:
For he beholdeth himself, and goeth his way, and straightway forgetteth what manner of man he was.
From Easton's Bible Dictionary
Matthew George Easton, 1897