Musnad Ahmad 1017:44

Waki’ narrated to us, Sufyan narrated to us, from Alqamah ibn Marthad, from Sulayman ibn Buraydah, from his father, who said: When the Messenger of Allah (peace and blessings of Allah be upon him) would appoint a commander over a detachment or an army, he would advise him regarding his own self to fear Allah, and regarding those who were with him among the Muslims to treat them well. He would say: "Fight in the name of Allah, in the path of Allah. Fight those who disbelieve in Allah. When you meet your enemy from among the polytheists, invite them to one of three traits or qualities. Whichever of them they respond to you with, accept it from them and refrain from them: Invite them to Islam; if they respond to you, accept it from them. Then invite them to move from their land to the land of the Emigrants (Muhajirin), and inform them that if they do that, they shall have what the Emigrants have, and upon them shall be what is upon the Emigrants. If they refuse and choose their own land, inform them that they will be like the Bedouin Muslims; the ruling of Allah that applies to the believers applies to them, and they shall have no share in the spoils (fay) or the booty (ghanimah) unless they strive (jihad) alongside the Muslims. If they refuse, then invite them to pay the Jizyah. If they respond, accept it from them and refrain from them. But if they refuse, then seek the help of Allah, and then fight them."