“I heard Sa'd and Abu Bakrah both say that they heard directly from Muhammad ﷺ saying it and memorized: 'Whoever claims to belong to someone other than his father knowing the he is not his father, Paradise will be forbidden to him.”
سَمِعْتُ سَعْدًا وَأَبَا بَكْرَةَ وَكُلُّ وَاحِدٍ مِنْهُمَا يَقُولُ سَمِعَتْ أُذُنَاىَ وَوَعَى قَلْبِي مُحَمَّدًا ﷺ يَقُولُ مَنِ ادَّعَى إِلَى غَيْرِ أَبِيهِ وَهُوَ يَعْلَمُ أَنَّهُ غَيْرُ أَبِيهِ فَالْجَنَّةُ عَلَيْهِ حَرَامٌ