Sunan Abu Dawud - سنن أبي داود
14. Fasting (Kitab Al-Siyam) - كتاب الصوم
53) Chapter: Regarding Continuous Voluntary Fasting
The tradition mentioned above has also been transmitted by Abu Qatadah through a different chain of narrators. This version add:
He said: Messenger of Allah, tell me about keeping fast on Monday and Thursday. He said: On it I was born, and on it the Qur'an was first revealed to me.
53) باب فِي صَوْمِ الدَّهْرِ تَطَوُّعًا
حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا مَهْدِيُّ، حَدَّثَنَا غَيْلاَنُ، عَنْ عَبْدِ اللَّهِ بْنِ مَعْبَدٍ الزِّمَّانِيِّ، عَنْ أَبِي قَتَادَةَ، بِهَذَا الْحَدِيثِ زَادَ قَالَ يَا رَسُولَ اللَّهِ أَرَأَيْتَ صَوْمَ يَوْمِ الاِثْنَيْنِ وَيَوْمِ الْخَمِيسِ قَالَ . " فِيهِ وُلِدْتُ وَفِيهِ أُنْزِلَ عَلَىَّ الْقُرْآنُ "
حكم: صحيح (الألباني)