If Muslims were to limit their imitation of Muhammad by brushing their teeth the way he did, Islam might have a legitimate place in the non-Muslim world. But Muslims cannot pick and choose. Once they believe that he was the “Messenger of God” -- the affirmation of faith contained in the shahada, the Muslim declaration of faith -- they are declaring their faith that everything he did was good because it was in furtherance of God’s cause -- including his violence against people who rejected him.
Muhammad’s body was reduced to dust nearly 14 centuries ago, but his spirit lives on in his Koran, which contains numerous incitements to violence against people who rejected him, and in the example of his behavior -- his sunna. Every time suicide bombers blow themselves up, killing other people along with them, there is Muhammad. When the 9/11 hijackers slammed their passenger airplanes into buildings, there was Muhammad in the cockpit with them. Just today, as 50 people fell to the machine gun bullets of a Muslim who walked into a nightclub in Orlando, Florida, and opened fire, the spirit of Muhammad hovered in the background, nodding with approval.
It's All About Muhammad