Narrator:Ibn al-Asqa
حَدَّثَنَا عَلِيُّ بْنُ عَيَّاشٍ، حَدَّثَنَا حَرِيزٌ، قَالَ حَدَّثَنِي عَبْدُ الْوَاحِدِ بْنُ عَبْدِ اللَّهِ النَّصْرِيُّ، قَالَ سَمِعْتُ وَاثِلَةَ بْنَ الأَسْقَعِ، يَقُولُ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم "
إِنَّ مِنْ أَعْظَمِ الْفِرَى أَنْ يَدَّعِيَ الرَّجُلُ إِلَى غَيْرِ أَبِيهِ، أَوْ يُرِيَ عَيْنَهُ مَا لَمْ تَرَ، أَوْ يَقُولُ عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم مَا لَمْ يَقُلْ "
Wāthilah ibn al-Asqa‘ (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "From the gravest of lies is someone who ascribes himself to other than his biological father, or claims to have seen something in a dream which he actually never saw, or ascribes something to the Messenger of Allah (may Allah's peace and blessings be upon him) which he did not say."
Reported by Al-Bukhari (No. 3509) and Ahmad (No. 16366).