Wakefulness and sobriety do not exhaust the demands made upon the Christian. He is also to be on his guard. "Put on the breastplate of faith and love; and for a helmet, the hope of salvation." While waiting for the Lord's coming, the Christian waits in a hostile world. He is exposed to assault from spiritual enemies who aim at nothing less than his life, and he needs to be protected against them. In the very beginning of this letter we came upon the three Christian graces; the Thessalonians were commended for their work of faith, labour of love, and patience of hope in the Lord Jesus Christ. There they were represented as active powers in the Christian life, each manifesting its presence by some appropriate work, or some notable fruit of character; here they constitute a defensive armour by which the Christian is shielded against any mortal assault. We cannot press the figure further than this. If we keep our faith in Jesus Christ, if we love one another, if our hearts are set with confident hope on that salvation which is to be brought to us at Christ's appearing, we need fear no evil; no foe can touch our life. It is remarkable, I think, that both here and in the famous passage in Ephesians, as well as in the original of both in Isaiah lix. 17, salvation, or, to be more precise, the hope of salvation, is made the helmet. The Apostle is very free in his comparisons; faith is now a shield, and now a breastplate; the breastplate in one passage is faith and love, and in another righteousness; but the helmet is always the same. Without hope, he would say to us, no man can hold up his head in the battle; and the Christian hope is always Christ's second coming. If He is not to come again, the very word hope may be blotted out of the New Testament. This assured grasp on the coming salvation--a salvation ready to be revealed in the last times--is what gives the spirit of victory to the Christian even in the darkest hour. The mention of salvation brings the Apostle back to his principal subject. It is as if he wrote, "for a helmet the hope of salvation; salvation, I say; for God did not appoint us to wrath, but to the obtaining of salvation through our Lord Jesus Christ." The day of the Lord is indeed a day of wrath,--a day when men will cry to the mountains and to the rocks, Fall on us, and hide us from the face of Him that sitteth upon the throne, and from the wrath of the Lamb; for the great day of their wrath is come. The Apostle cannot remember it for any purpose without getting a glimpse of those terrors; but it is not for these he recalls it at this time. God did not appoint Christians to the wrath of that day, but to its salvation,--a salvation the hope of which is to cover their heads in the day of battle.