The Word as Weapon

He must hold firm to the trustworthy word as taught, so that he may be able to give instruction in sound doctrine and also to rebuke those who contradict it
(Titus 1:9 ESV)

Luther preaching on the above text:

It is written in the book of Nehemiah that the Jews, in rebuilding Jerusalem, wrought with one hand and with the other held the sword, because of the enemy who sought to hinder their efforts.

Paul in Titus 1:9 carries out this thought in this teaching that a bishop, a pastor, or a preacher, should be mighty in the Holy Scriptures to instruct and admonish, as well as to resist the deniers. Accordingly, we are to make a twofold use of the Word of God: as both bread and weapon; for feeding and for resisting; in peace and in war. With one hand we must build, improve, teach and feed all Christendom; with the other, oppose the devil, the heretics, the world. For where the pasture is not defended, the devil will soon destroy it; he is bitterly opposed to God's Word. 

Let us then, God granting us his grace, so handle the Gospel that not only shall the souls of men be fed, but men shall learn to put on that Gospel as armour and fight their enemies. Thus shall it furnish both pasture and weapons.