The Prophet (may Allah's peace and blessings be upon him) informed the Companions that Muslims would win victory over the Jews of Khaybar the following day at the hands of a man to whom he would give the banner, which is the flag the army takes as its slogan. Among the traits of this man is that he loves Allah and His Messenger and Allah and His Messenger love him. So, the Companions spent their night conversing and talking about the one who would be given the banner, hoping to win that great honor. In the morning, they went to the Prophet (may Allah's peace and blessings be upon him), each wishing to be the one who would win that honor. The Prophet (may Allah's peace and blessings be upon him) asked about ‘Ali ibn Abi Tālib. It was said: He is sick suffering from sore eyes. So, he (may Allah's peace and blessings be upon him) sent for him, and when they brought him, he spat his honorable saliva into ‘Ali's eyes and supplicated for him. ‘Ali thus recovered from his sickness as if he had suffered no pain at all. Then he gave him the banner and ordered him to proceed gently until approaching the enemy's fortress, and he should then invite them to Islam. In case they respond to him, he should inform them of what is obligatory upon them. Then, the Prophet (may Allah's peace and blessings be upon him) clarified to ‘Ali the merit of calling people to Allah and the fact that if the preacher succeeds in guiding one single person, that will be better for him than having red camels, which represent the Arabs' most precious property, to possess or give out in charity.
- Superiority of ‘Ali ibn Abi Tālib (may Allah be pleased with him) and the Prophet's testimony for him that he is loved by Allah and His Messenger and that he loves Allah and His Messenger.
- The Companions' keenness to pursue goodness and their competing in doing good deeds.
- It is a Shariah directive to adhere to good manners in fight, and give up rashness and needless disturbing voices.
- Foretelling victory over the Jews and healing the eyes of ‘Ali ibn Abi Tālib, by Allah's permission, are among the signs of the Prophet's prophethood.
- Making people embrace Islam is the greatest purpose behind Jihad.
- Preaching should be carried out gradually, so the disbeliever should be at first asked to embrace Islam by pronouncing the Two Testimonies of Faith, and then he should be commanded to perform the obligations of Islam.
- The merit of calling to Islam and the good it entails for the one called and the caller, as the former might be granted guidance and the latter would be greatly rewarded.
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