Answer
(Fatwa: 1781/L=642/TL=1433)
(1) No hadith of Bukhari Sharif says ‘it is necessary to read fatiha behind the imam’. However, both types of traditions do exist i.e. to recite surah al-Fatiha or keep quiet behind the imam. Some Imams follow those traditions in which it is allowed to read fatiha behind imam. While Imam Abu Hanifa (رحمة الله عليه) follows the hadith in which it is forbidden to read surah al-Fatiha behind imam.
(2) Those verses and hadith which tell that reciting surah al-Fatiha is forbidden behind imam are as follows:
وَإِذَا قُرِئَ الْقُرْآنُ فَاسْتَمِعُواْ لَهُ وَأَنصِتُواْ . [الأعراف : 204]
Regarding this verse Hadhrat Abdullah ibn Abbas (رضى الله عنه) says that it was revealed for fardh salah.
Hadith: It is mentioned in Sahih Muslim that Hadhrat Abu Musa Asha’ri (رضى الله عنه) narrated that the holy Prophet Muhammad (صلى الله عليه وسلم) said: keep quiet when the imam recites. [Muslim Hadith No. 404]
عن أبي موسى الأشعري رضى الله عنه أن رسول الله صلى الله عليه وسلم خطبنا فبين لنا سنتنا وعلمنا صلاتنا فقال: إذا صليتم فأقيموا صفوفكم ثم ليؤم أحدكم فإذا كبر فكبروا ، وإذا قرأ فأنصتوا .
أخرجه مسلم (الصلاة / التشهد في الصلاة 404) وصححه وأخرجه أحمد (4/415) وأبوداؤد (الصلاة / التشهد 973)
There are many other hadith for which can be seen in books.
(4) You cannot make your uncle believe it, but you can show him these proofs, it is only Allah Who can make oneself believe.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband