O people! I charge you with ten rules; learn them well! Do not betray, or misappropriate any part of the booty; do not practice treachery or mutilation. Do not kill a young child, an old man, or a woman. Do not uproot or burn palms or cut down fruitful trees. Do not slaughter a sheep or a cow or a camel, except for food. You will meet people who have set themselves apart in hermitages; leave them to accomplish the purpose for which they have done this. You will come upon people who will bring you dishes with various kinds of foods. If you partake of them, pronounce God's name over what you eat. You will meet people who have shaved the crown of their heads, leaving a band of hair around it. Strike them with the sword. Go, in God's name, and may God protect you from sword and pestilence. - Abu Bakr, first Caliph