It is narrated from Anas bin Malik (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "I have been commanded to fight people until they bear witness to 'La ilaha illallah' (there is no god but Allah) and accept me as the Messenger of Allah. When they bear witness to the Oneness of Allah and to the Messengership, pray as we pray, face our qiblah in prayer and eat the animals we slaughter, then their blood and their wealth are forbidden to us except by a right due, and their reckoning rests with Allah Almighty."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2199