Sunan an-Nasai 17125
In-book no 2389أَخْبَرَنَا يَحْيَى بْنُ حَبِيبِ بْنِ عَرَبِيٍّ، قَالَ حَدَّثَنَا حَمَّادٌ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، أَنَّ حَمْزَةَ بْنَ عَمْرٍو الأَسْلَمِيَّ، سَأَلَ رَسُولَ اللَّهِ صلى الله عليه وسلم فَقَالَ يَا رَسُولَ اللَّهِ إِنِّي رَجُلٌ أَسْرُدُ الصَّوْمَ أَفَأَصُومُ فِي السَّفَرِ قَالَ " صُمْ إِنْ شِئْتَ أَوْ أَفْطِرْ إِنْ شِئْتَ " .
It was narrated from 'Aishah that Hamzah bin 'Amr Al-Aslami asked the Messenger of Allah: "O Messenger of Allah, I am a man who fasts continually: shoud I fast when traveling?" He said: "Fast if you wish and break you fast if you wish." 'Ata said: "someone who heard him told me that Ibn 'Umar (said) that the Prophet said: 'Whoever fasts every day of his life, and then he has not fasted."