This singular form designates a live coal, appearing in Isaiah's throne vision (6:6) where a seraph uses tongs to take a burning coal from the altar and touch the prophet's lips for purification. The coal's heat matters—it's not ash but active fire, potent enough to cauterize sin. The image combines danger and cleansing: what could destroy instead sanctifies. Though lexically related to H7529, this refers to glowing coals rather than heated baking stones.