Mishkat al-Masabih
‘A'isha said that Hamza b. ‘Amr al-Aslami who was greatly devoted to fasting asked the Prophet (ﷺ) whether he should fast when on a journey, and received the reply, “Fast if you like, or break your fast if you like.” (Bukhari and Muslim.)
وَعَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: إِنَّ حَمْزَةَ بْنَ عَمْرٍو الْأَسْلَمِيَّ قَالَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَصُومُ فِي السَّفَرِ وَكَانَ كَثِيرَ الصِّيَامِ. فَقَالَ: «إِنْ شِئْتَ فَصم وَإِن شِئْت فَأفْطر»
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