1) The story describes the lineage of Muhammad (peace be upon him) beginning with Abraham and his son Ishmael who settled in Mecca.
2) It tells of how 'Abd al-Muttalib, a descendant of Ishmael, rediscovered the lost well of Zamzam after having a dream, fulfilling a vow to sacrifice one of his future ten sons to Allah in thanks.
3) The Ka'bah, originally built by Abraham and Ishmael, had become surrounded by idols but was still an important site for pilgrimage.