Hadith: Take advantage of the concessions that Allah has granted you

عن جابر بن عبد الله رضي الله عنهما قال: «كان رسول الله صلى الله عليه وسلم في سفر. فَرَأَى زِحَامًا وَرَجُلًا قد ظُلِّلَ عليه، فقال: ما هذا؟ قالوا: صائم. قال: لَيْسَ مِنَ البِرِّ الصِّيَامُ فِي السَّفَرِ»، وفي لفظ لمسلم: « عَلَيْكُمْ بِرُخْصَةِ الله الَّذِي رَخَّصَ لكم».
[صحيح] - [متفق عليه]

Jābir ibn ‘Abdullāh (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) was on a journey and saw a crowd of people, and a man was being shaded (by them). He asked: "What is the matter with that (man)?" They said: "He is fasting." Thereupon, he said: "It is not from righteousness to fast when traveling." In another narration by Muslim, he said: "Take advantage of the concessions that Allah has granted you."
Sahih/Authentic. - [Al-Bukhari and Muslim]

Explanation

Jābir (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) during his journey in the year of the Conquest of Makkah in Ramadan, he saw people crowded together, and a man was lying down and being shaded by the crowd, as it reported in the narration of Ibn Jarīr. So, the Prophet (may Allah's peace and blessings be upon him) asked them about that man. They told him that he was fasting and reached such a state of thirst that he needed to lie down. So, the Prophet (may Allah's peace and blessings be upon him) said that one's fasting when traveling is not from righteousness, rather Muslims should take advantage of the concessions that Allah has granted them. Allah does not want us to punish ourselves by performing acts of worship.