708. hadíth
وَ رَوَى مُحَمَّدُ بْنُ مُسْلِمٍ عَنْ أَبِي جَعْفَرٍ عَلَيْهِ اَلسَّلاَمُ قَالَ: "لاَ تُصَلَّى خَلْفَ مَنْ يَبْغِي عَلَى اَلْأَذَانِ وَ اَلصَّلاَةِ بِالنَّاسِ أَجْراً وَ لاَ تُقْبَلُ شَهَادَتُهُ".
And Muhammad ibn Muslim narrated from Abu Ja'far Imam Muhammad ibn Ali Al-Baqir (a.s), who said: "Do not pray behind one who seeks payment for the call to prayer and leading people in prayer, and his testimony is not accepted."