So the prayer in congregation for the follower is voluntary, and the prayer of the individual before it is obligatory, and the evidence that the saying of the Prophet, peace and blessings be upon him: "There is no prayer after Fajr until the sun rises," is a specific prohibition, not a general prohibition.

Sayyiduna Yazid bin Aswad Amiri رضي الله عنه narrates that I participated in the Hajj with the Messenger of Allah صلى الله عليه وسلم. I performed the Fajr prayer with him in the Mosque of Khaif in Mina. When he صلى الله عليه وسلم completed the prayer, suddenly he saw that there were two men sitting behind the people who had not prayed with him. He صلى الله عليه وسلم ordered that both of them be brought to him. So they were brought, and (due to fear) the flesh of their shoulders was trembling. He صلى الله عليه وسلم asked: "Why did you not pray with us?" Both replied, "O Messenger of Allah صلى الله عليه وسلم, we have already prayed in our neighborhood." He صلى الله عليه وسلم said: "Do not do so. When you have prayed in your neighborhood (mosque), then if you come to a mosque where there is congregation, join them in prayer, for it will become a voluntary prayer for you." In the narration of Janab Bundar, it is stated: "Then come to the Imam who has not yet prayed." And in the narration of Janab Waki', it is stated: "Then come while the people are praying." And Janab San'ani has added these words: People were holding the blessed hand of the Prophet صلى الله عليه وسلم and placing it on their faces, and it was cooler than ice and more fragrant than musk.