It was narrated that Jabir ibn ‘Abdillah said: Mu‘adh would pray with the Prophet (blessings and peace of Allah be upon him), then he would go to his people and lead them in prayer..
Commentary :
The Sahabah (may Allah be pleased with them) were highly motivated in worship and in fulfilling their duties towards people and striving to benefit them. Jabir ibn ‘Abdillah (may Allah be pleased with him) narrated in this hadith that Mu‘adh ibn Jabal (may Allah be pleased with him) used to pray with the Messenger of Allah (blessings and peace of Allah be upon him). The prayer that he prayed with him was ‘Isha’, as is mentioned in other reports, and his people used to wait for him until he came and led them in praying ‘Isha’. The scholars differed with regard to how we may understand the fact that Mu‘adh prayed ‘Isha’ twice, because in principle the obligatory prayer cannot be done twice except for a reason. This is because of the hadith narrated by Abu Dawud from Sulayman ibn Yasar, that he heard the Messenger of Allah (blessings and peace of Allah be upon him) say: “… Do not pray any prayer twice in one day.” It was said that it may be that that was what Mu‘adh (may Allah be pleased with him) did at the beginning of Islam, when those who had knowledge of Qur’an were few, and the people had no one to lead them in prayer except Mu‘adh, so he would pray the obligatory prayer with the Messenger of Allah (blessings and peace of Allah be upon him), then he would go to his people and lead them in prayer, with the prayer being supererogatory in his case, as it says in a report narrated by al-Tahhawi in Sharh Ma‘ani al-Athar, from Jabir ibn ‘Abdillah (may Allah be pleased with him), in which it says: Mu‘adh used to pray ‘Isha’ with the Prophet (blessings and peace of Allah be upon him), then he would go to his people and lead them in ‘Isha’ prayer, and it would be a voluntary prayer for him and an obligatory prayer for them.
And it was said that it may be that this was done at a time when it was permissible to offer an obligatory prayer twice; that may have been done at the beginning of Islam, until the Prophet (blessings and peace of Allah be upon him) forbade it, and it is well-known that forbidding a thing usually comes after it has been permissible.
This hadith indicates that it is permissible for one who is praying an obligatory prayer to pray behind one who is offering a supererogatory prayer..