13. Ṣawm (Fasting)
١٣۔ كتاب الصيام
Do not observe fast for a day, or two days ahead of Ramadan except a person who is in the habit of observing a particular fast; he may fast on that day.
قَالَ رَسُولُ اللَّهِ ﷺ لاَ تَقَدَّمُوا رَمَضَانَ بِصَوْمِ يَوْمٍ وَلاَ يَوْمَيْنِ إِلاَّ رَجُلٌ كَانَ يَصُومُ صَوْمًا فَلْيَصُمْهُ
This hadith has been narrated on the authority of Yahya b. Abi Kathir with the same chain of transmitters.
عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ بِهَذَا الإِسْنَادِ نَحْوَهُ