Narrated Mu'adh:

I was a companion rider of the Prophet on a donkey called 'Ufair. The Prophet asked, "O Mu'adh! Do you know what Allah's right on His slaves is, and what the right of His slaves on Him is?" I replied, "Allah and His Apostle know better." He said, "Allah's right on His slaves is that they should worship Him (Alone) and should not worship any besides Him. And slave's right on Allah is that He should not punish him who worships none besides Him." I said, "O Allah's Apostle! Should I not inform the people of this good news?" He said, "Do not inform them of it, lest they should depend on it (absolutely)."

حَدَّثَنِي إِسْحَاقُ بْنُ إِبْرَاهِيمَ، سَمِعَ يَحْيَى بْنَ آدَمَ، حَدَّثَنَا أَبُو الأَحْوَصِ، عَنْ أَبِي إِسْحَاقَ، عَنْ عَمْرِو بْنِ مَيْمُونٍ، عَنْ مُعَاذٍ ـ رضى الله عنه ـ قَالَ كُنْتُ رِدْفَ النَّبِيِّ ﷺ عَلَى حِمَارٍ يُقَالُ لَهُ عُفَيْرٌ، فَقَالَ " يَا مُعَاذُ، هَلْ تَدْرِي حَقَّ اللَّهِ عَلَى عِبَادِهِ وَمَا حَقُّ الْعِبَادِ عَلَى اللَّهِ ". قُلْتُ اللَّهُ وَرَسُولُهُ أَعْلَمُ. قَالَ " فَإِنَّ حَقَّ اللَّهِ عَلَى الْعِبَادِ أَنْ يَعْبُدُوهُ وَلاَ يُشْرِكُوا بِهِ شَيْئًا، وَحَقَّ الْعِبَادِ عَلَى اللَّهِ أَنْ لاَ يُعَذِّبَ مَنْ لاَ يُشْرِكُ بِهِ شَيْئًا ". فَقُلْتُ يَا رَسُولَ اللَّهِ، أَفَلاَ أُبَشِّرُ بِهِ النَّاسَ قَالَ " لاَ تُبَشِّرْهُمْ فَيَتَّكِلُوا ".