A man from among the people of Najd with disheveled hair came to the Messenger of Allah ﷺ. The humming sound of his voice could be heard but what he was saying could not be understood. He came closer and it was then known that he was asking about Islam. The Messenger of Allah ﷺ said: Five times of prayer each day and night: He asked: Must I observe any more than them? He replied: No, unless you do it voluntarily. He (Talhah) said that the Messenger of Allah ﷺ mentioned fasting during the month of Ramadan. He asked: Must I observe anything else? He replied: No, unless you do it voluntarily. The Messenger of Allah ﷺ mentioned Zakat to him. He asked: Must I pay anything else? He replied: No, unless you do it voluntarily. The man then turned away saying: I swear by Allah, I shall not add anything to this or fall short of it. The Messenger of Allah ﷺ said: The man will be successful if he speaks truth. (Using translation from Abū Dāʾūd 391)
أَنَّهُ سَمِعَ طَلْحَةَ بْنَ عُبَيْدِ اللهِ يَقُولُ جَاءَ رَجُلٌ إِلَى رَسُولِ اللهِ ﷺ مِنْ أَهْلِ نَجْدٍ ثَائِرَ الرَّأْسِ يُسْمَعُ دَوِيُّ صَوْتِهِ وَلَا يُفْهَمُ مَا يَقُولُ حَتَّى دَنَا فَإِذَا هُوَ يَسْأَلُ عَنِ الْإِسْلَامِ؟ فَقَالَ لَهُ رَسُولُ اللهِ ﷺ «خَمْسُ صَلَوَاتٍ فِي الْيَوْمِ وَاللَّيْلَةِ» قَالَ هَلْ عَلَيَّ غَيْرُهُنَّ؟ قَالَ «لَا إِلَّا أَنْ تَطَوَّعَ» قَالَ وَصِيَامُ شَهْرِ رَمَضَانَ قَالَ هَلْ عَلَيَّ غَيْرُهُ؟ قَالَ «لَا إِلَّا أَنْ تَطَوَّعَ» وَذَكَرَ لَهُ رَسُولُ اللهِ ﷺ الزَّكَاةَ قَالَ هَلْ عَلَيَّ غَيْرُهَا؟ قَالَ «لَا إِلَّا أَنْ تَطَوَّعَ» فَأَدْبَرَ الرَّجُلُ وَهُوَ يَقُولُ وَاللهِ لَا أَزِيدُ عَلَى هَذَا وَلَا أَنْقُصُ مِنْهُ قَالَ رَسُولُ اللهِ ﷺ «أَفْلَحَ إِنْ صَدَقَ» قَالَ لَنَا أَبُو عَبْدِ الرَّحْمَنِ أَبُو سُهَيْلٍ هُوَ عَمُّ مَالِكِ بْنِ أَنَسٍ وَاسْمُهُ نَافِعُ بْنُ مَالِكِ بْنِ أَبِي عَامِرٍ الْأَصْبَحِيُّ وَهُوَ أَحَدُ الثِّقَاتِ