If imaam is in Fajar prayer and someone comes late, can he first offer sunnat two rakaat first and then join the Imaam?
Answer:
Dear brother if a believer enters into the masjid and finds that the congregation has already started, then he should immediately join the congregation, because in Islam obligatory(fard) prayer takes precedence over voluntary (sunnah ) prayer.How ever if a believer has started his Sunnah prayer and he fears that he may miss some portion of fard prayer then he should leave his Sunnah prayer & should join congregation and there will be absolutely no harm in leaving sunnah prayer for fard prayer.
In fajar prayer the believer can offer his missed Sunnah prayer after the prohibited time (zawal time).
Narrated Abu Said Al Khudri: I heard Allah's Messenger (pbuh) saying, "There is no prayer after fajr prayer till the sun rises, and there is no prayer after the Asr prayer till the sun sets." [Sahih Al-Bukhari Vol.1 Hadith No.586]
And Allah alone knows the best.
