from Shahr ibn Ḥawshab, from Ibn ʿAbbās, who said:
“A group of Jews once came to the Prophet—may Allah bless him and grant him peace—and said, ‘O Messenger of Allah, relate to us certain matters we wish to ask you about, matters that only a prophet could know.’
He replied, ‘Ask me whatever you like, but first grant me the pledge of Allah—and the pledge that Jacob exacted from his sons—that if I inform you of something you recognize as true, you will follow me in Islam.’
They answered, ‘That pledge is yours.’
He said, ‘Then ask whatever you wish.’
They said, ‘Tell us about four things: first, the food that Israel (Jacob) made unlawful for himself before the Torah was revealed; second, about a man’s fluid—how does a boy come from it until he is a boy, and how does a girl come from it until she is a girl; third, describe to us how this Prophet sleeps; and fourth, who is your guardian among the angels?’
He said, ‘You are now bound by Allah’s covenant and His solemn pledge—if I answer you, you will follow me.’ So they gave him whatever covenant and pledge he required.
He then declared, ‘I adjure you by the One who sent down the Torah to Moses: do you know that Israel—meaning Jacob—fell seriously ill, and that his illness lasted a long time, so he vowed to Allah that if Allah cured him he would forbid himself the drink he loved most and the food he loved most? His favorite drink was camel milk, and his favorite food was camel meat.’
They said, ‘By Allah, yes.’
The Messenger of Allah, peace and blessings be upon him, said, ‘O Allah, bear witness against them.’
He continued, ‘I adjure you…’