What are the merit and wisdom of the friday prayer?
The Friday prayer was made obligatory upon believers when the Prophet Muhammad was in the Ranuna Valley near Medina during his migration to Medina. Moreover, the first Friday sermon was delivered there in the Bani Salim Mosque.
Islam has always encouraged Muslims to pray altogether in a congregation. Therfore, for some of the prayers to be carried out, the congregation (jama’ah) has been put forth as a precondition.
The Jumu’ah prayer is fard upon all Muslim men who have the required qualities. When the call for prayer is announced, it is required for all those who are responsible to leave whatever they are occupied with and quickly go to the mosque in order to perform the Friday prayer.
When Muslims hear the muezzin reciting the call for the Jumu’ah prayer, they submit themselves to Allah’s following command; “O you who believe! When the call is proclaimed to prayer on Friday (the Day of Assembly), hasten earnestly to the Remembrance of Allah, and leave off business: That is best for you if ye but knew!”
Concerning those who pray the Jumu’ah prayer, our Prophet stated the following: “He who took a bath and then came for Jumu’a prayer and then prayed what was fixed for him, then kept silence till the Imam finished the sermon, and then prayed along with him, his sins between that time and the next Friday would be forgiven, and even of three days more.’”
Jumu’ah is the weekly religious festival of the Muslim community. For this reason, “the Prophet peace be upon him has forbidden fasting on Friday”.
It is recommended (mustahab) to show great care for the Jumu’ah prayer, to bathe and clean oneself, to cut the nails, to brush the teeth, to put on sweet fragrances, and to wear pleasant and clean clothes when going to the mosque. Abu Said-i Hudri (r.a) said the following:
I witness that the Allah’s Messenger (pbuh) ordered: “Taking a bath on Friday is compulsory for every male Muslim who has attained the age of puberty and (also) the cleaning of his teeth with Siwak, and the using of perfume if it is available.”
 Al-Jumu’a, 62: 9.
 Muslim, Jumu’a, 8
 Al-Bukhari, sawm 63; Muslim, siyam 145, 146
 Al-Bukhari, Jumu’a 4, 6; Muslim Jumu’a 10, 26.