The Sword of the Spirit is different from the other parts of the Armor of God in that it is not actually armor. It's a weapon, made to destroy rather than to protect. There are ways that you can use a sword defensively; you can block with a sword, and you can (literally) disarm your opponents with a sword, as Ammon did, without actually taking their lives, but by design, swords were made to slash, to stab, and to kill.
For this reason, I didn't like to think of Paladins as wielding swords. If I were a Paladin, I'd like to be a protector of the innocent rather than a slayer of the wicked. If I had the choice, I'd let the wicked live in hopes that they'd repent before they're sent to meet their maker. For that, I'd have to fight them with a weapon with which I could knock them out without killing them. A hammer would be good for this. But every time the word of God is described as a weapon, the weapon is a sword.
For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart. (Hebrews 4:12)
In early March, I described our testimonies as being useful as swords and shields in the war against evil. Then, I said that we could use our testimonies as swords by sharing our testimonies. We could teach the word of God, and declare our belief in it. This wouldn't hurt anyone like a real sword would, but it would be a good way to actively work against Satan. Satan tries to fool people with lies. We can help them see through the lies by baring testimony of the truth. Satan is the real enemy, not the people he fools, and the Word of God is a powerful weapon against him.
In a way, this method of fighting against Satan is very "sharp," in that it can cut through one thing while leaving a thing next to it unharmed. It can speak strongly against sin without condemning the sinner. You don't get that kind of accuracy with a hammer (I know. I tried it last night. That nail was almost impossible to hit). A sword can be a weapon of great precision, if it is sharp enough and wielded well.
Though I still would prefer to wield a hammer than a sword if the war against evil turned physical, I can see why, in a battle against spiritual evil, a sword is the best weapon for the job. The word of God was meant to pierce deep into our souls and touch our hearts, not to beat us over the head as with a club. The word of God is more gentle than that, and at the same time, more powerful. Paul knew what he was talking about when he compared God's word to a sword.