Alarmed at the bold part which the Prophet and his followers were now able to assume, and roused by the return of the deputies from Abyssinia and the announcement of their unsuccessful mission, the Quraish determined to check by a decisive blow any further progress of Islam. Towards this end, in the seventh year of the mission, they made a solemn covenant against the descendants of Hashim and Muttalib, engaging themselves to contract no marriage with any of them and to have no communication with them. Upon this, the Quraish became divided into two factions, and the two families of Hashim and Muttalib all repaired to Abu Talib as their chief. Abu Lahab, the Prophet's uncle, however, out of his inveterate hatred of his nephew and his doctrine, went over to the opposite party, whose chief was Abu Sufyan Ibn Harb, of the family of Umayya. The persecuted party, Muslims as well as idolaters, betook themselves to a defile on the eastern skirts of Mecca. They lived in this defensive position for three years. The provisions which they had carried with them were soon exhausted. Probably they would have entirely perished but for the sympathy and occasional help received from less bigoted compatriots.