"...If the party liable is mentally deficient, or weak, or unable Himself to dictate, Let his guardian dictate faithfully, and get two witnesses, out of your own men, and if there are not two men, then a man and two women, such as ye choose, for witnesses, so that if one of them errs, the other can remind her. The witnesses should not refuse when they are called on (For evidence)." - Quran 2:282 (read more)

"Narrated Anas bin Malik: While we were sitting with the Prophet in the mosque, a man came riding on a camel. He made his camel kneel down in the mosque, tied its foreleg and then said: "Who amongst you is Muhammad?" At that time the Prophet was sitting amongst us (his companions) leaning on his arm. We replied, "This white man reclining on his arm." They then addressed him" - Sahih Bukhari 1:3:63 (read more)

"Other scholars said Q. 2:256 has not been abrogated, but it had a special application. It was revealed concerning the people of the Book [the Jews and the Christians]; they can not be compelled to embrace Islam if they pay the Jizia (that is head tax on free non-Muslims under Muslim rule). It is only the idol worshippers who are compelled to embrace Islam and upon them Q. 9:73 applies ['O Prophet, struggle with the unbelievers and hypocrites, and be thou harsh with them.']. This is the opinion of Ibn 'Abbas which is the best opinion due to the authenticity of its chain of authority." - Al-Nahas