III. Their holy zeal to excite others to the same devotion (v. 15); they encourage their fellow-sufferers to do likewise. 1. Those who are in the fires, in the furnace of affliction, those fires by which the inhabitants of the earth are burned, v. 6. Or in the valleys, the low, dark, dirty places. 2. Those who are in the isles of the sea, whither they are banished, or are forced to flee for shelter, and hide themselves remote from all their friends. They went through fire and water (Ps. lxvi. 12); yet in both let them glorify the Lord, and glory him as the Lord God of Israel. Those who through grace can glory in tribulation ought to glorify God in tribulation, and give him thanks for their comforts, which abound as their afflictions do abound. We must in every fire, even the hottest, in every isle, even the remotest, keep up our good thoughts of God. When, though he slay us, yet we trust in him—when, though for his sake we are killed all the day long, yet none of these things move us—then we glorify the Lord in the fires. Thus the three children, and the martyrs that sang at the stake.