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»
Aishah said that Hamza ibn Amr al-Aslami who was greatly devoted to fasting asked the Prophet (sallallahu alayhi wa sallam) whether he should fast when on a journey, and received the reply, “Fast if you like, or break your fast if you like.”
Mishkat al-Masabih 1929, Book 8, Fasting, Hadith 63. 1 min read