Al-A'mash recited “on Friday” with the mim unvowelled, whereas the majority recited it with a dammah.

Scholars differed over why this day is called Jumu'ah. Some said: because Allah, Most High, brought Adam’s creation together on it. Others said: because Allah, Most High, completed the creation of all things on it, and the created beings came together upon it. Others said: because congregations gather on it. And others said: because people gather on it for prayer.

It is also said that the first to call it Jumu'ah was Ka'b ibn Lu'ayy. Abu Salamah said: “The first to say, ‘To proceed,’ was Ka'b ibn Lu'ayy; he was also the first to call Jumu'ah by this name. It had formerly been called the Day of al-Arubah.”

Ibn Sirin related: “The people of Madinah gathered before the Prophet, peace and blessings be upon him, came to Madinah, and before Surah al-Jumu'ah was revealed. They were the ones who named it Jumu'ah. They said: ‘The Jews have a day on which they gather every seven days, and the Christians have a day as well. So come, let us designate a day on which we may gather, remember Allah, and pray.’ They said: ‘Saturday belongs to the Jews and Sunday to the Christians, so make it the Day of al-Arubah.’ They then gathered around As'ad ibn Zurarah, who led them in two rak'ahs and admonished them. Thus, they called it Jumu'ah, after which Allah, exalted is He, revealed concerning it (1).

It is related from Abd al-Rahman ibn Ka'b ibn Malik, from his father Ka'b, that whenever he heard the call to prayer on Friday, he would invoke Allah’s mercy for As'ad ibn Zurarah. I said to him, “Whenever you hear the call to prayer, you invoke Allah’s mercy for As'ad ibn Zurarah?” He replied, “Because he was the first to lead us in the Friday prayer at Hazm al-Nabit, in the Harrah of Banu Bayadah, at a place called Baqi al-Khadimat.” I asked him, “How many of you were there that day?” He said, “Forty.” (2)

The first Friday prayer which the Messenger of Allah, peace and blessings be upon him, held with his Companions, according to the reports of the biographers, was when the Prophet, peace and blessings be upon him, arrived in Madinah as an emigrant. He stayed at Quba among Banu Amr ibn Awf. This was on a Monday, when twelve [nights] (3) of Rabi al-Awwal had elapsed, as the forenoon advanced. He remained at Quba on Monday, Tuesday, Wednesday, and Thursday, and laid the foundations of their mosque. Then, on Friday, he departed from among them, heading for Madinah. The Friday prayer overtook him among Banu Salim ibn Awf, in the middle of one of their valleys. A mosque now stands at that place. He held the Friday prayer there and delivered a sermon (4).