فَيَجُوزُ صَوْمُهُ بِنِيَّةٍ مِنَ اللَّيْلِ.
Translation: It is valid to fast it with an intention made at night.
For a time-fixed obligatory fast, intention may be formed during the preceding night. Here “the night” is the night immediately leading into the fast, not an unrelated earlier day.
Intention is an inward determination. Pronouncing a fixed Arabic formula is not a prerequisite; the person should know that they intend the next day’s fast.
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Kitab al-Sawm: Categories of Fasting and Rules of Intention
فَيَجُوزُ صَوْمُهُ بِنِيَّةٍ مِنَ اللَّيْلِ.
Translation: It is valid to fast it with an intention made at night.
For a time-fixed obligatory fast, intention may be formed during the preceding night. Here “the night” is the night immediately leading into the fast, not an unrelated earlier day.
Intention is an inward determination. Pronouncing a fixed Arabic formula is not a prerequisite; the person should know that they intend the next day’s fast.