Hadith.2586 - Muhammad ibn al-Qasim al-Astarabadi narrated to me from Yusuf ibn Muhammad ibn Ziyad and Ali ibn Muhammad ibn Yasar, from their fathers, from al-Hasan ibn Ali ibn Muhammad ibn Ali ibn Imam Musa ibn Jafar Al-Kadhim ibn Muhammad ibn Ali ibn al-Husayn ibn Ali ibn Abi Talib, from his father, from his forefathers, from Commander of the Faithful Imam Ali ibn Abi Talib عليه السلام, who said:
“The Messenger of Allah سبحانه وتعالى (peace be upon him and his family) said:
When Allah سبحانه وتعالى, the Almighty and Majestic, sent Musa ibn Imran عليه السلام and chose him as His confidant, parted the sea for him, saved the Children of Israel, and granted him the Torah and the Tablets, Musa saw his position before his Lord عز وجل, the Almighty, and said:
'O Lord عز وجل, You have honored me with an honor that You have not bestowed upon anyone before me.'
Allah سبحانه وتعالى, Glorified and Exalted, replied: 'O Musa, do you not know that Muhammad (peace be upon him and his family) is more virtuous in My sight than all My angels and all My creation?'
Musa then said: 'O Lord عز وجل, if Muhammad is more honored in Your sight than all of Your creation, is there anyone among the families of the Prophets more honored than my family?'"
Allah سبحانه وتعالى, the Almighty and Majestic, said:
"O Musa, do you not know that the excellence of the family of Muhammad over all the families of the Prophets is like the excellence of Muhammad over all the messengers?"
Musa said: "O Lord عز وجل, if the family of Muhammad is like that, then is there any nation among the nations of the Prophets more virtuous in Your sight than my nation, for whom You shaded the clouds, sent down manna and quails, and parted the sea?"
Allah سبحانه وتعالى, the Almighty, replied: "O Musa, do you not know that the excellence of the nation of Muhammad over all nations is like his excellence over all My creation?"
Musa said: "O Lord عز وجل, I wish I could see them."
Allah سبحانه وتعالى revealed to him: "O Musa, you will not see them, for this is not their time of appearance. But you will see them in Paradise, in the Gardens of Eden and Al-Firdaws, in the company of Muhammad, enjoying its delights and rejoicing in its bounties. Would you like Me to let you hear their speech?"
Musa said: "Yes, O my God."
Allah سبحانه وتعالى, the Almighty, said: "Stand before Me, gird your loins, and stand like a humble servant before the Glorious King."
Musa did as he was commanded, and our Lord عز وجل, the Almighty, called out: "O nation of Muhammad!"
They all answered Him, even though they were still in the loins of their fathers and the wombs of their mothers:
"Labbayka Allah}umma Labbayk, Labbayka la sharika laka Labbayk, inna al-hamda wa al-ni'mata laka wa al-mulk, la sharika laka Labbayk."
Allah سبحانه وتعالى, the Almighty, made this response the slogan of Hajj.
(The narration is lengthy; we have included the relevant portion here. The full version has been presented in the commentary on the Quran.)