Musnad Ahmed: Hadith 1619

On the day of al-Khandaq, there was a man who was shielding himself with his shield, doing something like this with it; he would put it over his nose, then do something like this, and then put it down. I stretched mу hand out towards my quiver and took out a bloodstained arrow, which I placed on the string of my bow. When he did something like this, and lowered his shield, I shot the arrow. I have never forgotten how it hit the shield, and he (the man) fell and started kicking with his foot. The Prophet (ﷺ) of Allah smiled-I (the narrator] think he said: so broadly that his eyeteeth could be seen- I said: Why? He said: Because of what that man did.