The seraphim appear in the vision Nephi quotes from Isaiah, in which Isaiah sees the Lord seated on a high throne in the temple (2 Nephi 16:1). Above the throne stood the seraphim, each with six wings: two covering the face, two covering the feet, and two with which to fly (2 Nephi 16:2). The name comes from a Hebrew root meaning “to burn.”
One seraph called to another, “Holy, holy, holy, is the Lord of Hosts; the whole earth is full of his glory,” and the posts of the door moved while the house filled with smoke (2 Nephi 16:3-4). When Isaiah confessed that he was a man of unclean lips, one of the seraphim flew to him with a live coal taken with tongs from the altar, laid it on his mouth, and said his iniquity was taken away and his sin purged (2 Nephi 16:5-7).