"Fight those who believe not in Allah or the Last Day, nor hold that forbidden which hath been forbidden by Allah and His Messenger, nor acknowledge the religion of Truth, (even if they are) of the People of the Book, until they pay the jizya with willing submission, and feel themselves subdued." - Quran 9:29 (read more)

"Narrated Anas: The climate of Medina did not suit some people, so the Prophet ordered them to follow his shepherd, i.e. his camels, and drink their milk and urine (as a medicine). So they followed the shepherd that is the camels and drank their milk and urine till their bodies became healthy. Then they killed the shepherd and drove away the camels. When the news reached the Prophet he sent some people in their pursuit...." - Sahih Bukhari 1:5:268 (read more)

"The Qur’aan, Sunnah and ijmaa’ (scholarly consensus) all indicate that we must differ from the kuffaar in all aspects and not imitate them, because imitating them on the outside will make us imitate them in their bad deeds and habits, and even in beliefs, which will result in befriending them in our hearts, just as loving them in our hearts will lead to imitating them on the outside." - Shaykh Al-Islam ibn Taymiyyah