The Prophet of Mercy Website

Al-Muhajireen battalion, under the command of Mus‘ab bin ‘Umair Al-‘Abdari.
Al-Ansari-Aws battalion was commanded by Usaid bin Hudair.
Al-Ansari-Khazraj battalion with Al-Hubab bin Al-Mundhir to lead it.
The army consisted of a thousand fighters; a hundred of them armoured; another fifty horsemen. He appointed Ibn Umm Maktum to lead the people in prayer in Madinah. Departure was announced and the army moved northwards with the two Sa‘ds, who were armoured, running in front of the army.

Upon passing along Al-Wada‘ mountain trail he saw a well-armed battalion, which were detached from the main body of the army. The Prophet (Peace be upon him) inquired who they were and he was told that they were Jews and were allies of Al-Khazraj. They told him that they wanted to contribute to the fight against the idolaters. “Have they embraced Islam?” The Prophet (Peace be upon him) asked. “No,” they said. So he refused admitting them and said that he would not seek the assistance of disbelievers against the idolaters.

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