To observe Saum continuously day and night (Al-Wisal) till the time of Sahar.
باب الْوِصَالِ إِلَى السَّحَرِ
Sahih al-Bukhari, Book of Fasting(view book)
Sahih al-Bukhari 1967
Narrated Abu Said Al-Khudri:
Allah's Apostle ﷺ said, "Do not fast continuously day and night (practise Al-Wisal) and if anyone of you intends to fast continuously day and night, he should continue till the Suhur time." They said, "But you practise Al-Wisal, O Allah's Apostle!" The Prophet ﷺ said, "I am not similar to you;
. during my sleep I have One Who makes me eat and drink."
حَدَّثَنَا إِبْرَاهِيمُ بْنُ حَمْزَةَ، حَدَّثَنِي ابْنُ أَبِي حَازِمٍ، عَنْ يَزِيدَ، عَنْ عَبْدِ اللَّهِ بْنِ خَبَّابٍ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ ـ رضى الله عنه ـ أَنَّهُ سَمِعَ رَسُولَ اللَّهِ ﷺ يَقُولُ " لاَ تُوَاصِلُوا، فَأَيُّكُمْ أَرَادَ أَنْ يُوَاصِلَ فَلْيُوَاصِلْ حَتَّى السَّحَرِ ". قَالُوا فَإِنَّكَ تُوَاصِلُ، يَا رَسُولَ اللَّهِ. قَالَ " لَسْتُ كَهَيْئَتِكُمْ، إِنِّي أَبِيتُ لِي مُطْعِمٌ يُطْعِمُنِي وَسَاقٍ يَسْقِينِ ".