Musannaf Ibn Abi Shayba 19:874

Abu Bakr narrated to us, he said: Al-Fadl ibn Dukayn narrated to us, he said: Aban ibn Abdullah al-Bajali narrated to us, he said: Ibrahim ibn Jarir narrated to me, from Jarir, who said: "The Prophet of Allah sent me to Yemen to fight them and call them. If they say, 'There is no god but Allah,' their wealth and their blood become forbidden to you."