it was during the pilgrimage season, in the eleventh year of prophethood, that the islamic call found the righteous seeds through which it would grow up to constitute tall trees whose leaves would foster the new faith and shelter the new vulnerable converts from the blows of injustices and high-handness of quraish. it was the prophet’s wise practice to meet the delegates of the arabian tribes by night so that the hostile makkans would not debar him from achieving his objectives.[tareekh-e-islam p.129] in the company of his two truthful companions ‘ali and abu bakr, he had an interesting talk regarding islamization with bani dhuhal, but the latter suspended their conversion.[mukhtasar seerat ar-rasool p.150] in pursuit of the same objective, the prophet and his companions passed by ‘aqabat mina where they heard people talking. they went at their heels until they encountered six men from yathrib, all of whom from khazraj tribe: as‘ad bin zurarah, ‘awf bin harith, rafi‘ bin malik, qutbah bin ‘amir, ‘uqbah bin ‘amir and jabir bin ‘abdullah. the last two being from aws and the former four from khazraj.
the madinese always heard the jews say that a prophet was about to rise, for the time for a new dispensation had arrived. him they would follow and then smite their enemies as the children of ‘ad and iram had been smitten. [rahmat-al-lil'alameen 1/84; ibn hisham 1/429; za'd al-ma'ad 2/50]
"of what tribe are you?" asked the prophet. "of the tribe of khazraj," they replied. "are you the allies of the jews?" the prophet enquired. they said: "yes." "then why not sit down for a little and i will speak to you." the offer was readily accepted for the fame of muhammad [pbuh] had spread to madinah and the strangers were curious to see more of the man who had created a stir in the whole area. the prophet [pbuh] presented to them an expose of islam, explained its implications, and the responsibilities that fell upon the men who accepted it. when the prophet [pbuh] concluded his talk, they exchanged among themselves ideas to the following effect: "know surely, this is the prophet with whom the jews are ever threatening us; wherefore let us make haste and be the first to join him."
they, therefore, embraced islam, and said to the prophet, "we have left our community for no tribe is so divided by hatred and rancour as they are. allâh may cement our ties through you. so let us go and invite them to this religion of yours; and if allâh unites them in it, no man will be dearer than you."
the handful of madinese converts remained steady to the cause and they preached the islam with full zeal and devotion with the result that they succeeded in winning adherents for islam from amongst their fellow citizens and hardly was there a house in madinah not talking curiously and enthusiastically about the messenger of allâh [pbuh]. [ibn hisham 1/428-430]