The Prophet (ﷺ) sent a Sariya of spies and appointed `Asim bin Thabit, the grandfather of `Asim bin
`Umar bin Al-Khattab, as their leader. So they set out, and when they reached (a place) between
'Usfan and Mecca, they were mentioned to one of the branch tribes of Bani Hudhail called Lihyan. So,
about one-hundred archers followed their traces till they (i.e. the archers) came to a journey station
where they (i.e. `Asim and his companions) had encamped and found stones of dates they had brought
as journey food from Medina.
The archers said, "These are the dates of Medina," and followed their traces till they took them over.
When `Asim and his companions were not able to go ahead, they went up a high place, and their
pursuers encircled them and said, "You have a covenant and a promise that if you come down to us,
we will not kill anyone of you." `Asim said, "As for me, I will never come down on the security of an
infidel. O Allah! Inform Your Prophet about us." So they fought with them till they killed `Asim along
with seven of his companions with arrows, and there remained Khubaib, Zaid and another man to
whom they gave a promise and a covenant. So when the infidels gave them the covenant and promise,
they came down. When they captured them, they opened the strings of their arrow bows and tied them
with it. The third man who was with them said, "This is the first breach in the covenant," and refused
to accompany them. They dragged him and tried to make him accompany them, but he refused, and
they killed him. Then they proceeded on taking Khubaib and Zaid till they sold them in Mecca. The
sons of Al-Harith bin `Amr bin Naufal bought Khubaib. It was Khubaib who had killed Al-Harith bin
`Amr on the day of Badr. Khubaib stayed with them for a while as a captive till they decided
unanimously to kill him. (At that time) Khubaib borrowed a razor from one of the daughters of Al-
Harith to shave his pubic hair. She gave it to him. She said later on, "I was heedless of a little baby of
mine, who moved towards Khubaib, and when it reached him, he put it on his thigh.
When I saw it, I got scared so much that Khubaib noticed my distress while he was carrying the razor
in his hand. He said 'Are you afraid that I will kill it? Allah willing, I will never do that,' " Later on she
used to say, "I have never seen a captive better than Khubaib Once I saw him eating from a bunch of
grapes although at that time no fruits were available at Mecca, and he was fettered with iron chains,
and in fact, it was nothing but food bestowed upon him by Allah." So they took him out of the
Sanctuary (of Mecca) to kill him. He said, "Allow me to offer a two-rak`at prayer." Then he went to
them and said, "Had I not been afraid that you would think I was afraid of death, I would have prayed
for a longer time." So it was Khubaib who first set the tradition of praying two rak`at before being
executed. He then said, "O Allah! Count them one by one," and added, 'When I am being martyred as
a Muslim, I do not care in what way I receive my death for Allah's Sake, because this death is in
Allah's Cause. If He wishes, He will bless the cut limbs." Then `Uqba bin Al-Harith got up and
martyred him. The narrator added: The Quraish (infidels) sent some people to `Asim in order to bring
a part of his body so that his death might be known for certain, for `Asim had killed one of their chiefs
on the day of Badr. But Allah sent a cloud of wasps which protected his body from their messengers
who could not harm his body consequently.
Sahih al-Bukhari Book 64, Hadith 130
"Abdul-'Aziz bin 'Abdul-Malik bin Abu Mahdhurah narrated from 'Abdullah bin muhairiz who was an orphan under the care of Abu Mahdhurah bin mi'yar that when he was preparing him to travel to Sham, he said: 'O my uncle, I am going out to Sham, and I will be asked about how you started the Adhan.' So he informed me that. Abu Mahdhurah said: 'I went out with a group of people, and we were somewhere on the road, when the Mu'adh-dhin of the Messenger of Allah gave the call to prayer in the presence of the Messenger of Allah. We heard the voice of the Mu'adh-dhin, and we were shunning it (the Adhan), so we started yelling, imitating it and mocking it. The Messenger of Allah heard us, so he sent some people who brought us to sit in front of him. He said: 'Who is the one whose voice I heard so loud?' The people all pointed to me, and they were telling the truth. He sent them all away, but kept me there and said to me: 'Stand up and give the call to prayer.' I stood up and there was nothing more hateful to me than the Messenger of Allah and what he was telling me to do. I stood up in front of the Messenger of Allah and the Messenger of Allah himself taught me the call. He said: "Say: 'Allahu Akbar Allahu Akbar, Allahu Akbar Allahu Akbar; Ash-hadu an la ilaha illallah, Ash-hadu an la ilaha illallah; Ash-hadu anna Muhammadan Rasulullah, Ash-hadu anna Muhammadan Rasulullah (Allah is the Most great, Allah is the most Great, Allah is the most Great, Allah is the most Great; I bear witness that none has the right to be worshipped but Allah, I bear witness that none has the right to be worshipped but Allah; I bear witness that Muhammad is the Messenger of Allah, I bear witness that Muhammad is the Messenger of Allah).'" Then he said: "Raise your voice (and say). Ash-hadu an la ilaha illallah, Ash-hadu an la ilaha illallah; Ash-hadu anna Muhammadan Rasulullah, Ash-hadu anna Muhammadan Rasulullah; Hayya 'alal-salah, Hayya 'alal-salah; Hayya 'alal-falah, Hayya 'alal-falah; Allahu Akbar Allahu Akbar; La ilaha illallah (I bear witness that none has the right to be worshipped but Allah, I bear witness that none has the right to be worshipped but Allah; I bear witness that Muhammad is the Messenger of Allah, I bear witness that Muhammad is the Messenger of Allah; Come to the Prayer, Come to the Prayer; Come to the prosperity, Come to the prosperity; Allah is the Most great, Allah is the Most Great; None has the right to be worshipped but Allah).'" Then he called me when I had finished saying the Adhan, and gave me a small bag in which there was some silver. Then he put his hand on the forelock of Abu Mahdhurah, then passed it over his face, then over his chest, and over his heart, until the hand of the Messenger of Allah reached his navel. Then the Messenger of Allah said: 'May Allah bless you and send blessings upon you.' I said: 'O Messenger of Allah, do you command me to give the call to prayer in Makkah?' He said: 'Yes, I command you (to do so).' Then all the hatred I had felt towards the Messenger of Allah disappeared, and was replaced with love for the Messenger of Allah. I came to 'Attab bin Asid, the governor of the Messenger of Allah in Makkah, and gave the call to prayer with him by command of the Messenger of Allah." (Sahih)He ('Abdul-'Aziz) said: "Someone who met Abu Mahdhurah told me the same as 'Abdullah bin Muhairiz told me."
Sunan Ibn Majah Book 3, Hadith 3
"The Messenger of Allah (ﷺ) said: 'Allah, the Mighty and Sublime, enjoined fifty prayers upon my Ummah, and I came back with that until I passed by Musa, peace be upon him, who said: 'What has your Lord enjoined upon your Ummah?' I said: 'He has enjoined fifty prayers on them.' Musa said to me: 'Go back to your Lord, the Mighty and Sublime, for your Ummah will not be able to do that.' So I went back to my Lord, the Mighty and Sublime, and He reduced a portion of it. Then I came back to Musa and told him, and he said: 'Go back to you Lord, for your Ummah will not be able to do that.' So I went back to my Lord, the Mighty and Sublime, and He said: 'They are five (prayers) but they are fifty (in reward), and the Word that comes from Me cannot be changed.' I came back to Musa and he said: 'Go back to your Lord.' I said: 'I feel too shy before my Lord, the Mighty and Sublime.'"
See Surah Qaf 50:29.
Sunan an-Nasa'i Book 5, Hadith 2