Martin Luther constantly talked about the power of God’s Word. This theme came up in his famous hymn that we’ve all heard: “That Word above all earthly powers…one little Word shall fell him.” Here’s part of a sermon Luther gave on Luke 11:14-28; in it he talked about God’s powerful Word. Look for Luther’s excellent straw illustration/analogy:
“…We should never speak in a derogatory or careless way about God’s Word…. True it is that the preached Word is but an ordinary Word and the people who preach it are but ordinary people. But when it emanates from Christ’s command to preach it and is coupled with faith, then it possesses the kind of power that can make the devil flee. God has set his almighty power in a very lowly instrument and a very fragile vessel. Against Satan we human beings are but straw, so that were he able to unleash his power against us he would demolish us in a flash. So what does God do? He kindles a little flame against this arrogant, mighty spirit, that is, he puts his Word in the straw’s mouth, and that selfsame word is a heavenly fire which, wherever it goes, scorches the devil, so that he doesn’t know where to run.”
“That is indeed an almighty power, as St. Paul calls it in Romans 1:16, able to save those who believe on it. It has the power and might of God and is able to bring people out of sin to righteousness, from death to life, from hell to heaven, out of the devil’s kingdom into the kingdom of God, to save them. Surely there is no more wonderful, mighty power than that of the Word, which empowers the poor straw with such potency that it can drive Satan away and free those who believe it from sin and death, and bring them righteousness and everlasting life.”
-From a sermon Luther preached on the Third Sunday in Lent, 1534; found in Luther’s Sermons, volume 5, pages 342-3.