A:
if you find two people offering a congregational obligatory Salah and you like to join them, you along with the Ma’mum are to step backward and pray behind the Imam (the one who leads congregational Prayer). However, it is also permissible that the Imam steps forward and you both keep your place behind him. Proof for the foregoing is the Hadith related by Muslim and Abu Dawud to the effect that the Prophet (peace be upon him) directed the two Sahabys (Companions of the Prophet) Jabir and Jabbar to pray behind him.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.