رِيَاضُ الصَّالِحِينَ
Riyad as-Salihin 1259
The Book of Virtues
The Desirability of Observing Three Days of Fasting in Every Month
وَعَنْ أَبِي الدَّرْدَاءِ رَضِيَ اللَّهُ عَنْهُ قَالَ: أَوْصَانِي حَبِيبِي، صَلَّى اللَّه عَلَيْهِ وَسَلَّمَ بِثَلاَثٍ لَنْ أَدَعَهُنَّ مَا عِشْتُ: بِصِيَامِ ثَلاَثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ، وَصَلاَةِ الضُّحَى، وَبِأَنْ لاَ أَنَامَ حَتَّى أُوتِرَ. ((رَوَاهُ مُسْلِم)).
Abud-Darda (May Allah be pleased with him) reported: My friend (the Messenger of Allah) (ﷺ) directed me to observe Saum (fasting) for three days in every month, to perform two Rak'ah (optional) Duha prayer at forenoon, and to perform the Witr prayer before going to bed. [Al-Bukhari and Muslim].
Riyad as-Salihin, 1259