 The Quraish, however, did not succeed in killing Muhammad, and did not attempt to occupy the town of Medina, possibly because they knew it was guarded by Ibn Ubayy.Rodinson suggests that the Meccans did not want to reforge the very unity of the population, which had been jeopardised by Muhammad's defeat.Ibn Ubay was also involved in Muhammad's conflict with another Jewish tribe, the Banu Nadir.