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 نَسْمَعُ دَوِيَّ صَوْتِهِ وَلَا نَفْقَهُ مَا يَقُولُ حَتَّى دَنَا مِنْ رَسُولِ اللهِ ﷺ فَإِذَا هُوَ يَسْأَلُ عَنِ الْإِسْلَامِ فَقَالَ رَسُولُ اللهِ ﷺ خَمْسُ صَلَوَاتٍ فِي الْيَوْمِ وَاللَّيْلَةِ فَقَالَ هَلْ عَلَيَّ غَيْرُهُنَّ؟ قَالَ لَا إِلَّا أَنْ تَطَوَّعَ فَقَالَ رَسُولُ اللهِ ﷺ وَصِيَامُ شَهْرِ رَمَضَانَ قَالَ هَلْ عَلَيَّ غَيْرُهُ؟ قَالَ لَا إِلَّا أَنْ تَطَوَّعَ قَالَ وَذَكَرَ لَهُ رَسُولُ اللهِ ﷺ الزَّكَاةَ قَالَ هَلْ عَلَيَّ غَيْرُهَا؟ قَالَ لَا إِلَّا أَنْ تَطَوَّعَ فَأَدْبَرَ الرَّجُلُ وَهُوَ يَقُولُ وَاللهِ لَا أَزِيدُ عَلَى هَذَاِ وَلَا أَنْقُصُ مِنْهُ فَقَالَ رَسُولُ اللهِ ﷺ أَفْلَحَ إِنْ صَدَقَ قَالَ الشَّافِعِيُّ ؓ فِي حَدِيثِهِ وَذَكَرَ الصَّدَقَةَ فَقَالَ هَلْ عَلَيَّ غَيْرُهَا مُخَرَّجٌ فِي الصَّحِيحَيْنِ مِنْ حَدِيثِ مَالِكٍ