But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up. The day of the Lord will come - See Matthew 24:43, to which the apostle seems to allude.
The heavens shall pass away with a great noise - As the heavens mean here, and in the passages above, the whole atmosphere, in which all the terrestrial vapours are lodged; and as water itself is composed of two gases, eighty-five parts in weight of oxygen, and fifteen of hydrogen, or two parts in volume of the latter, and one of the former; (for if these quantities be put together, and several electric sparks passed through them, a chemical union takes place, and water is the product; and, vice versa, if the galvanic spark be made to pass through water, a portion of the fluid is immediately decomposed into its two constituent gases, oxygen and hydrogen); and as the electric or ethereal fire is that which, in all likelihood, God will use in the general conflagration; the noise occasioned by the application of this fire to such an immense congeries of aqueous particles as float in the atmosphere, must be terrible in the extreme. Put a drop of water on an anvil, place over it a piece of iron red hot, strike the iron with a hammer on the part above the drop of water, and the report will be as loud as a musket; when, then, the whole strength of those opposite agents is brought together into a state of conflict, the noise, the thunderings, the innumerable explosions, (till every particle of water on the earth and in the atmosphere is, by the action of the fire, reduced into its component gaseous parts), will be frequent, loud, confounding, and terrific, beyond every comprehension but that of God himself.
The elements shalt melt with fervent heat - When the fire has conquered and decomposed the water, the elements, στοιχεια, the hydrogen and oxygen airs or gases, (the former of which is most highly inflammable, and the latter an eminent supporter of all combustion), will occupy distinct regions of the atmosphere, the hydrogen by its very great levity ascending to the top, while the oxygen from its superior specific gravity will keep upon or near the surface of the earth; and thus, if different substances be once ignited, the fire, which is supported in this case, not only by the oxygen which is one of the constituents of atmospheric air, but also by a great additional quantity of oxygen obtained from the decomposition of all aqueous vapours, will rapidly seize on all other substances, on all terrestrial particles, and the whole frame of nature will be necessarily torn in pieces, and thus the earth and its works be burned up.