Serpent, brazen means in the bible: Moses gave it to God at God’s order as a sacramental way of healing the Israelites living in Num. 21:9. It appears to have been well preserved, and it became an object for superstitious worship 2 kms. 18:4 and it was destroyed by Hezekiah who called it Nehushtan. The Lord refers to the “lifting of” the serpent in wilderness as an example of His “lifting up” upon the cross John 3:14-15. The Latter-day revelation confirms that the incident of fiery serpents occurred and also the healing properties associated looking at Moses’ brazen serpent 1N. 17:41; 2 Ne. 25:20, Alma 33:19-22 and 37:46
(in Bible Dictionary)