Fasting
30/20. Chapter:
Sahur is a blessing but it is not compulsory
لأَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَأَصْحَابَهُ وَاصَلُوا وَلَمْ يُذْكَرِ السَّحُورُ.For the Prophet ﷺ and his companions kept observing fasting continuously for more than one day and (of course) no Sahur (late night meals) was taken (during that prolonged fast).
Sahih Bukhari
حَدَّثَنَا آدَمُ بْنُ أَبِي إِيَاسٍ، حَدَّثَنَا شُعْبَةُ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ صُهَيْبٍ، قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ ـ رضى الله عنه ـ قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم " تَسَحَّرُوا فَإِنَّ فِي السَّحُورِ بَرَكَةً ".
Narrated Anas bin Malik: The Prophet (ﷺ) said, "Take Suhur as there is a blessing in it."
Reference : Sahih al-Bukhari 1923In-book reference : Book 30, Hadith 32USC-MSA web (English) reference : Vol. 3, Book 31, Hadith 146