Wathila ibn al-Asqa’ reported: The Messenger of Allah, peace and blessings be upon him, said, “The scriptures of Abraham, upon him be peace, were revealed on the first night of Ramadan. The Torah was revealed after six nights of Ramadan had passed. The Gospel was revealed after thirteen nights of Ramadan had passed. The Quran was revealed after twenty four nights of Ramadan had passed.”
Source: Musnad Aḥmad 16536
Grade: Hasan (fair) according to Al-Albani
عَنْ وَاثِلَةَ بْنِ الْأَسْقَعِ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ أُنْزِلَتْ صُحُفُ إِبْرَاهِيمَ عَلَيْهِ السَّلَام فِي أَوَّلِ لَيْلَةٍ مِنْ رَمَضَانَ وَأُنْزِلَتْ التَّوْرَاةُ لِسِتٍّ مَضَيْنَ مِنْ رَمَضَانَ وَالْإِنْجِيلُ لِثَلَاثَ عَشْرَةَ خَلَتْ مِنْ رَمَضَانَ وَأُنْزِلَ الْفُرْقَانُ لِأَرْبَعٍ وَعِشْرِينَ خَلَتْ مِنْ رَمَضَانَ
16536 مسند أحمد مسند الشاميين
1575 المحدث الألباني خلاصة حكم المحدث إسناده حسن رجاله ثقات في السلسلة الصحيحة