Heat is a metaphor in the Bible. It is a metaphor of extreme suffering. The psalmist who underwent extreme suffering describes it as being wax melted by the heat. He complains, 'I am poured out like water, and all my bones are out of joint; my heart is like wax; it is melted within my breast' (Psalm 22:14 ESV).
Another psalmist uses a similar metaphor to describe his self-inflicted pain. 'For when I kept silent, my bones wasted away throughmy groaning all day long. For day and night your hand was heavy upon me;my strength was dried up as by the heat of summer' (Ps 32:3,4 ESV).
Everyone seems to agree that heat is not good. The heat of suffering particularly. It brings anguish and pain. It drains the strength, it drains the sap. However, it has a positive side.
Heat purifies. The goldsmith heats up the precious metals in a crucible until they melt. In the molten stage, the gold separates itself from the impurities. It gains a new shine! Sometimes God raises the heat in our lives so that we may be pure! The gold has no right to know why the impurities are removed by this painful process. Enduring the process is difficult, but the hope of purity and the new shine it is going to have helps with patient enduring.
Though it may look paradoxical, heat reshapes. As a child, I have watched the village blacksmith heating up a piece of iron until it is red-hot and beat it up to a new shape. Then he dips it in water to temper it. Again to the furnace again to make it red-hot. The iron goes through the process repeatedly: heated up, beaten, and tempered in the cold water. Then after a few hours, the blacksmith holds the iron to admire his creation. It is a piece of art now, though the process was painful.
The iron has no right to know what it is going to be. It simply has to trust the creator. It just has to believe that it is going to change the shape, and then there is going to have a new use. Heat brings with it new hope and purpose.