"The last instruction that the Messenger of Allah gave to me was that I should not appoint a Mu'adh-dhin who took payment for the Adhan." (sahih)
كَانَ آخِرُ مَا عَهِدَ إِلَىَّ النَّبِيُّ ﷺ أَنْ لاَ أَتَّخِذَ مُؤَذِّنًا يَأْخُذُ عَلَى الأَذَانِ أَجْرًا
"Indeed, amount the last (of orders) Messenger of Allah ordered me with was to employ a Mu'adh-dhin who would not take a wage for his Adhan."
إِنَّ مِنْ آخِرِ مَا عَهِدَ إِلَىَّ رَسُولُ اللَّهِ ﷺ أَنِ اتَّخِذْ مُؤَذِّنًا لاَ يَأْخُذُ عَلَى أَذَانِهِ أَجْرًا
[Machine] "It was part of what the Messenger of Allah ﷺ entrusted to me that I do not take any payment for making the call to prayer."
كَانَ مِمَّا «عَهِدَ إِلَيَّ رَسُولُ اللهِ ﷺ أَنْ لَا آخُذَ عَلَى الْأَذَانِ أَجْرًا»
[Machine] The last thing the Prophet ﷺ said to me was, "Pray with your companions the prayer that is the most difficult for them, for among them are the elderly and the weak, and those in need, and appoint a Mu'adhin who does not take a wage for the call to prayer."
كَانَ آخِرُ مَا عَهِدَ إِلَيَّ النَّبِيُّ ﷺ قَالَ «صَلِّ بِأَصْحَابِكَ صَلَاةَ أَضْعَفِهِمْ فَإِنَّ فِيهِمُ الْكَبِيرَ وَالضَّعِيفَ وَذَا الْحَاجَةِ وَاتَّخِذْ مُؤَذِّنًا لَا يَأْخُذُ عَلَى الْأَذَانِ أَجْرًا»
"عَنْ عُثْمَانَ بْنِ أَبِى الْعَاصِى الثَّقفىِّ - ؓ -: كَانَ آخِرُ مَا عَهِدَ إِلَىَّ رَسُولُ اللهِ ﷺ أَنْ أَتَّخِذَ مُؤذِّنًا لا يَأخُذُ عَلَى أَذَانِهِ أَجْرًا".