burn·ing / ˈbərning/ • adj. on fire: a burning building. ∎  very hot or bright: burning desert sands. ∎ fig. very keenly or deeply felt; intense: he had a burning ambition to climb to the upper reaches of management. ∎ fig. of urgent interest and importance; exciting or calling for debate: democracy remains a burning issue.DERIVATIVES: burn·ing·ly adv.

burning burning bush in Exodus 3:2, a bush which ‘burned with fire, and…was not consumed’, seen by Moses on Mount Horeb, and constituting a sign from God that he was to lead the Israelites out of Egypt.
burning fiery furnace in Daniel ch. 3, the fire into which the three Hebrew exiles in Babylon, Shadrach, Meshach, and Abednego, were cast by King Nebuchadnezzar because they refused to worship pagan images, and in which they were preserved unharmed.