And prayers and peace be upon our Prophet Muhammad, and upon his family and all his Companions.

The reader: In the name of Allah, the Most Gracious, the Most Merciful.
Praise be to Allah, Lord of the worlds, and may peace and blessings be upon our Prophet Muhammad, and upon his family and all his Companions:
The author (may Allah have mercy on him) transmitted, in the context of the hadiths in the chapter on the virtue of congregational prayer: "From Ibn Mas'ud (may Allah be pleased with him), who said:

He who likes to meet Allah tomorrow (i.e., on the Day of Requital) as a Muslim, should take care and observe the Salat when the Adhan is announced for them. Allah has expounded to your Prophet (ﷺ) the ways of right guidance, and these (the prayers) are part of the right guidance. If you have to perform Salat in your houses, as this man who stays away (from the mosque) and performs Salat in his house, you will abandon the Sunnah (practice) of your Prophet (ﷺ), and the departure from the Sunnah of your Prophet (ﷺ) will lead you astray. I have seen the time when no one stayed behind except a well-known hypocrite. I also saw that a man was brought swaying (on account of weakness) between two men till he was set up in a row (in the mosque).

مَن سرَّه أن يلقى الله تعالى غدا مسلماً، فليحافظ على هؤلاء الصلوات حيث ينادى بهن، فإن الله شرع لنبيكم صلى الله عليه وسلم سُنن الهدى، وإنهنَّ مِن سُنن الهدى، ولو أنكم صليتم في بيوتكم كما يصلي هذا المتخلف في بيته، لتركتم سنة نبيكم، ولو تركتم سنة نبيكم، لضللتم، ولقد رأيتنا وما يتخلَّف عنها إلا منافق معلوم النفاق، ولقد كان الرجل يُؤتى به، يُهادى بين الرجلين حتى يقام في الصف

Riyad as-Salihin 1069

Narrated by Muslim.
And in a narration from him, he said:

He also said: God’s Messenger taught us the paths of right guidance, among which is prayer in the mosque in which the adhan is called.

إن رسول الله صلى الله عليه وسلم علمنا سُنن الهدى، وإن من سُنن الهدى الصلاة في المسجد الذي يؤذن فيه

Mishkat al-Masabih 1072

.
And from Abu al-Darda' (may Allah be pleased with him), who said: I heard the Messenger of Allah (peace and blessings be upon him) say:

If three men in a village or in the desert, make no arrangement for Salat in congregation, Satan must have certainly overcome them. So observe Salat in congregation, for the wolf eats up a solitary sheep that stays far from the flock.

ما مِن ثلاثة في قرية ولا بدو لا تقام فيهم الصلاة إلا قد استحوذ عليهم الشيطان، فعليكم بالجماعة، فإنما يأكلُ الذئبُ من الغنم القاصية

Riyad as-Salihin 1070

Narrated by Abu Dawud with a good chain of narration .

The Shaykh : In the name of Allah, the Most Gracious, the Most Merciful:
The author (may Allah have mercy on him) presented this report from 'Abdullah ibn Mas'ud (may Allah be pleased with him) in the chapter on the virtue of congregation. This report is as if it issues from the fountainhead of prophethood, meaning it is as if it is from the words of the Messenger (peace and blessings be upon him), in its smoothness, beauty, and arrangement. He (may Allah be pleased with him) said: This is because congregational prayer in the mosque is obligatory, so it is not permissible for anyone who is able to pray in the mosque to do so except that it is obligatory for him, if he is among those for whom congregation is obligatory, such as men.
Then he (may Allah be pleased with him) mentioned: : meaning the paths of guidance. So whatever the Prophet (peace and blessings be upon him and his family) brought is guidance and light that Allah prescribed for him. : meaning the five prayers. : And he (may Allah be pleased with him) spoke the truth. Indeed, the five prayers are the greatest of the sunnahs of guidance after the two testimonies, because prayer is the greatest pillar of Islam after the testimony that there is no god but Allah and that Muhammad is the Messenger of Allah.
Then he said: : meaning if everyone prayed in his home as this laggard prayed in his home, we would have abandoned the sunnah and the mosques would have been left empty, and people would have been cut off from one another, and they would not have gotten to know each other or formed bonds of affection, and this great manifestation of the Islamic religion would not have occurred if people each prayed in their homes. But out of the mercy and wisdom of Allah, He prescribed for the servants to pray in congregation, five times a day, meeting your brother, greeting him and he greets you, and following one imam. This is a great blessing. This is one of the greatest bonds of affection and love. Then he said: meaning: from these prayers in the mosques. : And the hypocrites are many, especially when Islam becomes strong. When Islam became strong and powerful, a person could not declare his disbelief. For this reason, hypocrisy did not manifest and did not increase in the time of the Messenger (peace and blessings be upon him) except when the Muslims were victorious in the Battle of Badr. When the Muslims were victorious in the Battle of Badr in the second year of the Hijrah, hypocrisy began to appear. The disbelievers feared for their lives, so they began to declare Islam, until they would come to the Messenger (peace and blessings be upon him and his family) and say: We testify that you are the Messenger of Allah. So Allah, the Exalted, said: : meaning they did not speak the truth; they said with their tongues what was not in their hearts.
He says: : Why does the hypocrite lag behind? Because the hypocrite does not hope for reward and does not believe in the Reckoning, so he does not care. For this reason, the Messenger (peace and blessings be upon him and his family) said: : Because the 'Isha' prayer is one where a person, if he lags behind in the time of the Messenger, there are no lights or electricity, so a person lags behind and it is not known about him. Then, the 'Isha' and Fajr prayers come at times of rest and sleep, so they are heavy for the hypocrites; they do not come to them. .
Then he (may Allah be pleased with him) mentioned that a man would be brought: : meaning held by two men, a sick man who cannot walk alone, they support him: they walk with him slowly until he is placed in the row and prays with the congregation. May Allah be pleased with them. And with these actions and the like, they possessed the east and west of the earth.
And when the Muslim community lagged behind and their hearts differed, they became what you see now: a humiliated nation, even though they number a billion people, and yet they are in the most humiliated state of all nations, because they are divided. Indeed, some are hostile to one another, and indeed, some see the other as more severe upon them than the Jews and the Christians, refuge with Allah from that, because they are disputing and divided. But in the time of the Messenger (peace and blessings be upon him), no one could lag behind the congregation, even if he was sick; he would be brought and supported between two men until he was placed in the row. So if we returned to what the Companions (may Allah be pleased with them) were upon, we would become a noble and honored nation, everyone would fear them, everyone would seek their favor, and everyone would be friendly toward them. We ask Allah to restore our glory in our religion, and to restore our honor. Indeed, He is capable of all things.