The Sacrifice of Hazrat Ismail (as)

 Imam Musa Ibn Ja‘far says that when Ibrahim was leaving Hajar and Isma‘il at Makkah, they began to lament.
“Why do you weep?” asked Ibrahim, “I am leaving you at a place that is most beloved one of Allah and the sanctuary (Haram) of Allah is also situated here?”
“I never expected this from a Prophet like you,” said Hajar.
“What did I do?” asked Ibrahim.
“You are leaving a helpless woman and a weak child in a place where there is no one to help them and there is neither vegetation and water nor any habitation.”
Upon hearing these words Ibrahim began to weep. He came to the door of Ka‘bah and said, “O My Lord! I have settled some of my progeny in a barren valley near Your Holy House, so that they may establish prayers. So I beg you to instill their love in the hearts of some people and they are attracted towards them; and grant them fruits in excess so that they be thankful to you.”
The Almighty Allah revealed to him that he should go atop the mountain of Abu Qubais and call the people for the hajj of Ka‘bah as ordered by Him. For the Ka‘bah is the Holy sanctuary of Allah in Makkah.
Thus Ibrahim scaled the peak of Abu Qubais and called out in his loud voice. The Almighty spread his call to the east and the west of the earth and all the people heard it. Even those who were in the loins of their father or in the wombs of their mother. Therefore hajj became incumbent for all the creatures from that time onwards. And the Talbiya (Reply) that the hajj chant is the reply to the call of Ibrahim, the call that he had issued under the Divine instructions.