It is not permissible to differ from the people of the city with regard to fasting and Eid

In our city there is a group of committed brothers, but they differ from us with regard to some matters, such as fasting in Ramadan. They do not fast until they see the moon with the naked eye. Sometimes we fast two or three days before them in Ramadan, and they break their fast one or two days after Eid al-Fitr. Every time we ask them about fasting on the day of Eid they say, “We do not break our fast or start to fast until we see the new moon with the naked eye, because the Prophet (peace and blessings of Allah be upon him) said, ‘Fast when you see it and break your fast when you see it.’” But they do not recognize the sighting of the moon with instruments as you know. They also differ with regard to the time of Eid prayer, and they do not pray until after Eid according to their sighting. Similarly on Eid al-Adha they differ from us with regard to offering the sacrifice of Eid and the standing at ‘Arafaah. They celebrate two days after Eid al-Adha, i.e., they do not offer the sacrifice until after all the Muslims have offered their sacrifices. Is what they are doing correct? May Allah reward you with good.