Questioner:

If a person sleeps before breaking the fast, and does not wake up until the morning of the following day, does he continue fasting or does he break it?

Shaykh Muqbil bin Hādī al-Wādiʿī:

He continues fasting, as occurred to Qays ibn Sarmah when he was working. During the initial stages when fasting became obligatory, if the person slept then it was not allowed for him to eat – meaning if he slept at night without eating then it was not allowed him to eat food. So Qays returned to his wife [after working] and asked, “Is there any food?” She replied, “No, but I will go a get some food for you.”.  So she returned and found him sleeping, she said to him “Your extinguished..” or “You have lost it [fallen asleep]” or something to this meaning.

Then he went and worked until mid-day until he fainted. Then Allah ﷻ revealed;

أُحِلَّ لَكُمْ لَيْلَةَ الصِّيَامِ الرَّفَثُ إِلَىٰ نِسَائِكُمْ ۚ هُنَّ لِبَاسٌ لَّكُمْ وَأَنتُمْ لِبَاسٌ لَّهُنَّ ۗ عَلِمَ اللَّهُ أَنَّكُمْ كُنتُمْ تَخْتَانُونَ أَنفُسَكُمْ فَتَابَ عَلَيْكُمْ وَعَفَا عَنكُمْ ۖ فَالْآنَ بَاشِرُوهُنَّ وَابْتَغُوا مَا كَتَبَ اللَّهُ لَكُمْ ۚ وَكُلُوا وَاشْرَبُوا حَتَّىٰ يَتَبَيَّنَ لَكُمُ الْخَيْطُ الْأَبْيَضُ مِنَ الْخَيْطِ الْأَسْوَدِ مِنَ الْفَجْرِ ۖ ثُمَّ أَتِمُّوا الصِّيَامَ إِلَى اللَّيْلِ ۚ
۞ وَلَا تُبَاشِرُوهُنَّ وَأَنتُمْ عَاكِفُونَ فِي الْمَسَاجِدِ ۗ تِلْكَ حُدُودُ اللَّهِ فَلَا تَقْرَبُوهَا ۗ كَذَ‌ٰلِكَ يُبَيِّنُ اللَّهُ آيَاتِهِ لِلنَّاسِ لَعَلَّهُمْ يَتَّقُونَ

“It is made lawful for you to have sexual relations with your wives on the night of Al-Saum (the fasts). They are Libās [i.e. body cover, or screen, or Sakan, (i.e. you enjoy the pleasure of living with her] for you and you are the same for them. Allāh knows that you used to deceive yourselves, so He turned to you (accepted your repentance) and forgave you. So now have sexual relations with them and seek that which Allāh has ordained for you (offspring), and eat and drink until the white thread (light) of dawn appears to you distinct from the black thread (darkness of night), then complete your Saum (fast) till the nightfall.” (Q 2:187)