Before the discovery of oxygen, it was commonly thought that burning involved the combustion of a mysterious and undetectable substance called "phlogiston." The rate at which substances burned depended on the amount of phlogiston they contained. This theory worked just fine until Joseph Priestly discovered oxygen and performed his famous demonstration with the oxidation of mercury. Priestly put a glob of mercury on the pan of a balance and using a lens he focused sunlight on it. The mercury burned under the intense heat, producing an orange powder, mercuric oxide. Miraculously there was an increase in weight. Now, if phlogiston had burned up, there should have been a loss in weight. Subsequent experiments by Lavoisier resulted in our modern theory of burning and the demise of the phlogiston theory.
Actually, most substances burn, or oxidize, even at low temperatures. For example, iron oxidizes or burns into rust at room temperature as does paint, paper, and other metals. In fact aluminum, which is usually considered a non-rusting metal, oxidizes into a white powder, and it is necessary to frequently polish the aluminized surface of telescope mirrors to remove this film. There are some metals that do not oxidize, such as gold and platinum, and they are called "noble metals." Ordinary steel will oxidize, but stainless steel contains elements that prevent oxidation.
When oxidation occurs rapidly to produce a flame, we call it combustion. The temperature at which combustion occurs is called the kindling temperature, and every substance has its own unique kindling temperature. For instance, ordinary newsprint paper has a kindling temperature of about 451 degrees Fahrenheit, from whence came the title of the movie, Fahrenheit 451. At the kindling temperature, substances will burst into flame spontaneously, from which comes the expression "spontaneous combustion." There have been cases where houses have been under construction, and the painters have carelessly left paint-soaked rags in attics. On a hot summer day these rags would spontaneously combust and cause serious fire damage.
There is one thing that has the highest kindling temperature of all, one that requires a fire that is hotter than any fire experienced by man. Satan and his angels have existed for over 6,000 years without access to the tree of life; they must have tremendous vitality to have survived this long. But God has determined that sin must be eradicated from the universe. To do so, He has prepared a special fire that is designed to destroy Satan, his angels, and all those who choose to follow him. This fire will be so hot that it reaches the kindling temperature of sin; it will be "the sin incinerator."
