وَأَصْلُهُ فِي
" اَلْمُتَّفَقِِ " مِنْ حَدِيثِ عَائِشَةَ; { أَنَّ حَمْزَةَ بْنَ عَمْرٍو سَأَلَ } 11 - صحيح. رواه البخاري ( 4 / 179 / فتح )، ومسلم ( 2 / 789 ) وتمامه: رسول الله صلى الله عليه وسلم عن الصيام في السفر، فقال: " إن شئت فصم، وإن شئت فافطر ".
And it's basic meaning is in Al-Bukhari and Muslim from the narration of Aisha (with the wording) "that Hamza bin 'Amro asked".
Hamzah bin ’Amro Al-Aslami (RAA) narrated, ‘I said to the Messenger of Allah (ﷺ) ‘O Messenger of Allah (ﷺ)! I find within me the strength to fast while traveling. Would there be any blame upon me if I were to do so?’ The Messenger of Allah (ﷺ) said to him, "It is a concession from Allah. Whoever takes it has done well. Whoever likes to fast, there is no blame upon him."Related by Muslim.
وَعَنِ اِبْنِ عَبَّاسٍ -رَضِيَ اَللَّهُ عَنْهُمَا- قَالَ: { رُخِّصَ لِلشَّيْخِ اَلْكَبِيرِ أَنْ يُفْطِرَ, وَيُطْعِمَ عَنْ كُلِّ يَوْمٍ مِسْكِينًا, وَلَا قَضَاءَ عَلَيْهِ } رَوَاهُ اَلدَّارَقُطْنِيُّ, وَالْحَاكِمُ, وَصَحَّحَاهُ 1 .1 - صحيح. رواه الدارقطني ( 2 / 205 / 6 )، والحاكم ( 1 / 440 )، وقال الدارقطني: وهذا الإسناد صحيح. وقال الحاكم: حديث صحيح على شرط البخاري.
Ibn ’Abbas (RAA) narrated, ‘An elderly man is permitted to break his fast, but he must feed a poor person daily, and he does not have to make up for it.’ Related by Ad-Daraqutni and Al- hakim, who rendered it to be Sahih
وَفِي لَفْظٍ: { فَقِيلَ لَهُ: إِنَّ اَلنَّاسَ قَدْ شَقَّ عَلَيْهِمُ اَلصِّيَامُ, وَإِنَّمَا يَنْظُرُونَ فِيمَا فَعَلْتَ، فَدَعَا بِقَدَحٍ مِنْ مَاءٍ بَعْدَ اَلْعَصْرِ، فَشَرِبَ } رَوَاهُ مُسْلِمٌ 1 .1 - حسن. وهذه الرواية في " مسلم " ( 1114 ) ( 91 )، ولكن لفظ: " فشرب" ليس في "الصحيح "، وإنما هو من أوهام الحافظ رحمه الله.
In another narration, ‘He was told that people are finding it difficult to fast (during the journey) and they are waiting to see what the Prophet (ﷺ) will do. So he called for a cup of water after the Asr (afternoon) prayer and drank it.’ Related by Muslim.