At-Tawbah 9:80
اسْتَغْفِرْ لَهُمْ أَوْ لَا تَسْتَغْفِرْ لَهُمْ إِن تَسْتَغْفِرْ لَهُمْ سَبْعِينَ مَرَّةً فَلَن يَغْفِرَ اللَّهُ لَهُمْ ۚ ذَٰلِكَ بِأَنَّهُمْ كَفَرُوا بِاللَّهِ وَرَسُولِهِ ۗ وَاللَّهُ لَا يَهْدِي الْقَوْمَ الْفَاسِقِينَ ٨٠
Istaghfir lahum aw la tastaghfir lahum in tastaghfir lahum sabAAeena marratan falan yaghfira Allahu lahum thalika biannahum kafaroo biAllahi warasoolihi waAllahu la yahdee alqawma alfasiqeena
Ask pardon for them, or ask not pardon for them; if thou askest pardon for them seventy times, God will not pardon them; that, because they disbelieved in God and His Messenger; God guides not the people of the ungodly. (9:80)
The Prohibition of asking for Forgiveness for Hypocrites
Allah says to His Prophet that hypocrites are not worthy of seeking forgiveness for them and that if he asks Allah to forgive them seventy times, Allah will not forgive them. The number seventy here was mentioned to close the door on this subject, for Arabs use this number when they exaggerate, not that they actually mean seventy or more than seventy. Ash-Sha`bi said that when `Abdullah bin Ubayy was dying, his son went to the Prophet and said to him, "My father has died, I wish you could attend him and pray the funeral prayer for him." The Prophet said,
«مَا اسْمُك»
("What is you name) He said, "Al-Hubab bin `Abdullah." The Prophet said,
«بَلْ أَنْتَ عَبْدُاللهِ بْنُ عَبْدِاللهِ إِنَّ الْحُبَابَ اسْمَ شَيْطَان»
(Rather, you are `Abdullah bin `Abdullah, for Al-Hubab is a devil's name.) The Prophet went along with him, attended his father's funeral, gave him his shirt as a shroud and prayed the funeral prayer for him. He was asked, "Would you pray on him, when he is a hypocrite" He said,
«إِنَّ اللهَ قَالَ:
إِن تَسْتَغْفِرْ لَهُمْ سَبْعِينَ مَرَّةً
وَلَأسْتَغْفِرَنَّ لَهُمْ سَبْعِينَ وَسَبْعِينَ وَسَبْعِين»
(Allah said,(...(and even) if you ask seventy times for their forgiveness...) Verily, I will ask Allah to forgive them seventy times and seventy more and seventy more.)" Similar narrations were collected from `Urwah bin Az-Zubayr, Mujahid, Qatadah bin Di`amah and Ibn Jarir.