And to Thamud We sent forth their brother. Salih. He said to them: 'O my people! Serve Allah, you have no other god than Him. Truly there has come to you a clear proof from your Lord. This she-camel from Allah is a Divine portent for you. So leave her alone to pasture on Allah's earth, and touch her with no evil lest a painful chastisement should seize you.