This depends what Bible you read from, some say molten glass & others say cast metal mirror.
Yes, I agree, and the NKJV which I usually quote from says "cast metal mirror." But all the versions I've seen say "sky" or "skies", and not "firmament."
The Bible Hub site includes:
"Adam Clarke was born in the county of Londonderry, North Ireland, in 1760 and was converted in 1779 through hearing a Methodist preacher. Three years later he left home to attend Wesley's school in Kingswood, Bristol, England. Five weeks later he was appointed to his first preaching circuit and for the next 50 years he was a self-taught Wesleyan preacher who, among other academic accomplishments, made himself master of at least 10 languages, ancient and modern.
He served on 24 Methodist circuits in England and Ireland, worked for 3 years in the Channel Islands, was three times president of the English Methodist Conference and four times president of the Irish Methodist Conference. He devoted hundreds of working hours to the newly founded British and Foreign Bible Society and 10 years of painstaking editing and collating of state papers. This latter work was a colossal undertaking. It required the most exact examination, deciphering, and classification of British State Papers from 1131 to 1666. The research was carried on in 14 different locations, including the Tower of London, London's Westminster Archives, and Cambridge University Library. In 1808 the University of Aberdeen conferred on Adam Clarke the honorary degree of LL.D., the university's highest academic honor.
As well as his Commentary, Clarke's publications ran to 22 volumes, including his Memorials of the Wesley Family, Reflections on the Being and Attributes of God, The Manners of the Ancient Israelites, 4 volumes of sermons, 3 volumes of miscellanea titled Detached Pieces, a volume on Christian Missions, A Concise View of the Succession of Sacred Literature, and A Bibliographical Dictionary. Clarke's literary output was phenomenal when it is recalled that he was a full-time itinerant preacher."
It is a verse that many flat earthers use plus Genesis 1:7 to present the truth about the firmament especially Rob skiba & Dean Odle & I believe them.
Another verse they use is;
The earth takes shape like clay under a seal; its features stand out like those of a garment. Job 38:14
I don't know why they use that verse, seeing that it does not include the word "firmament" (and the Hebrew does not include the word "raqia" either.
