Mu’adh ibn Jabal reported: The Messenger of Allah, peace and blessings be upon him, sent me to Yemen and he said, “Verily, you are going to people among the people of the Book, so call them to testify there is no God but Allah and I am the Messenger of Allah. If they accept that, then teach them that Allah has obligated five prayers in each day and night. If they accept that, then teach them that Allah has obligated charity to be taken from the rich and given to the poor. If they accept that, then beware not to take from the best of their wealth. Beware the supplication of the oppressed, for there is no veil between it and Allah.”
Source: Ṣaḥīḥ al-Bukhārī 4347, Ṣaḥīḥ Muslim 19
Grade: Muttafaqun Alayhi (authenticity agreed upon) according to Al-Bukhari and Muslim
عَنْ مُعَاذِ بْنِ جَبَلٍ قَالَ بَعَثَنِي رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ إِنَّكَ تَأْتِي قَوْمًا مِنْ أَهْلِ الْكِتَابِ فَادْعُهُمْ إِلَى شَهَادَةِ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَأَنِّي رَسُولُ اللَّهِ فَإِنْ هُمْ أَطَاعُوا لِذَلِكَ فَأَعْلِمْهُمْ أَنَّ اللَّهَ افْتَرَضَ عَلَيْهِمْ خَمْسَ صَلَوَاتٍ فِي كُلِّ يَوْمٍ وَلَيْلَةٍ فَإِنْ هُمْ أَطَاعُوا لِذَلِكَ فَأَعْلِمْهُمْ أَنَّ اللَّهَ افْتَرَضَ عَلَيْهِمْ صَدَقَةً تُؤْخَذُ مِنْ أَغْنِيَائِهِمْ فَتُرَدُّ فِي فُقَرَائِهِمْ فَإِنْ هُمْ أَطَاعُوا لِذَلِكَ فَإِيَّاكَ وَكَرَائِمَ أَمْوَالِهِمْ وَاتَّقِ دَعْوَةَ الْمَظْلُومِ فَإِنَّهُ لَيْسَ بَيْنَهَا وَبَيْنَ اللَّهِ حِجَابٌ
4347 صحيح البخاري كتاب المغازي باب بعث أبي موسى ومعاذ إلى اليمن قبل حجة الوداع
19 صحيح مسلم كتاب الإيمان باب الدعاء إلى الشهادتين وشرائع الإسلام