Al Qaadee ibn Samaa'ah said: For forty years I never missed the first Takbeer of the congregational prayers except on one occasion; my mother died and I missed it. So I got up and prayed twenty seven times in order to make up the reward.
When I slept, it was said to me in my dream; 'Indeed you have prayed, but what about the Angels saying Ameen?'
[i.e. he made up for the reward of the congregation by praying twenty seven times, as the congregational prayer is twenty seven times greater in reward than a prayer on your own, but how is he going to make up for the angels saying Ameen at the same time that the people in congregation say Ameen, as this cannot be made up when one prays on their own.]
On the authority of 'Ubaydullah ibn 'Umar al-Qawareeree , may Allah have mercy upon him, who said:
I never used to miss a prayer in congregation, but one time I had a guest and was preoccupied with hosting him so I missed the 'Ishaa at the Masjid. I left to pray with the congregation at the Masjid but found that all the Masaajid had finished the prayer and closed.
I returned home, feeling sad that I missed the congregation; I said to myself; In the Hadeeth it states that a prayer in congregation is better than twenty seventy prayers alone, so I prayed the 'Ishaa twenty seven times.
I went to sleep and saw myself in a dream riding a horse with other people in front of me also riding horses. I pushed my horse to catch up to them but I wasn't able to.
I looked at one of them, he said to me; 'Do not tire your horse, you will not be able to catch up with us!'
I said to him; 'Why, my brother?'
He said; 'Because we prayed the 'Ishaa in congregation and you prayed by yourself.'
So I woke up in a state of sadness and worry.
[Al-Waafee bil Wafayaat by as-Safde: 3/116]
Haatim al Asam said; I missed the prayer in congregation one time, and only Abu Ishaaq al Bukharee gave me his condolences. If a child of mine were to pass away, more than ten thousand people would have given me their condolences; a calamity regarding religion is lighter to the people than a calamity in worldly life.
[Az-Zawaahir 'an Irtikaab al-Kabaa-ir by al-Haythamee: 1/277]