Riyad as-Salihin, Book 18, Hadith 1802 (In-Book)

Sa'd bin Abu Waqqas (May Allah be pleased with him) said: The Prophet said, "He who (falsely) attributes his fatherhood to anyone besides his real father, knowing that he is not his father, will be forbidden to enter Jannah."[Al-Bukhari and Muslim].

عن سعد بن أبي وقاص رضي الله عنه أن النبي صلى الله عليه وسلم قال‏:‏ ‏ "‏من ادعى إلى غير أبيه وهو يعلم أنه غير أبيه، فالجنة عليه حرام‏" ‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏‏.‏

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