Sunan Ibn Majah, Volume 5, Book 36, Hadith 4070 (DarusSalam) ⓘ
It was narrated from Safwan bin ‘Assal that the Messenger of Allah said: “Towards the west (i.e., the place of the setting of the sun) there is an open door, seventy years wide. That door will remain open for repentance until the sun rises from this direction. When it rises from this direction, faith will not benefit any soul that did not believe before or earn anything good through its faith.”
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُوسَى، عَنْ إِسْرَائِيلَ، عَنْ عَاصِمٍ، عَنْ زِرٍّ، عَنْ صَفْوَانَ بْنِ عَسَّالٍ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " إِنَّ مِنْ قِبَلِ مَغْرِبِ الشَّمْسِ بَابًا مَفْتُوحًا عَرْضُهُ سَبْعُونَ سَنَةً فَلاَ يَزَالُ ذَلِكَ الْبَابُ مَفْتُوحًا لِلتَّوْبَةِ حَتَّى تَطْلُعَ الشَّمْسُ مِنْ نَحْوِهِ فَإِذَا طَلَعَتْ مِنْ نَحْوِهِ لَمْ يَنْفَعْ نَفْسًا إِيمَانُهَا لَمْ تَكُنْ آمَنَتْ مِنْ قَبْلُ أَوْ كَسَبَتْ فِي إِيمَانِهَا خَيْرًا " .
also referenced under: Hadith 4070 (Reference) & Book 36, Hadith 145 (In-Book)