Hamzah ibn ʿAmr al-Aslami enjoyed firm endurance and was physically able to fast; he loved doing good and was accustomed to frequent fasting (Allah be pleased with him). He therefore asked the Messenger of Allah ﷺ, “Should I fast while traveling?” The Prophet ﷺ gave him the choice, saying, “If you wish, then fast; and if you wish, then break your fast.”

Points derived from the ḥadīth
1- The concession to break the fast while traveling, since travel is a likely source of hardship.
2- A traveler who has the strength to fast may choose between fasting and breaking the fast. What is meant is the fast of Ramadan, as clarified by the report recorded by Abū Dāwūd and al-Ḥākim: Hamzah ibn ʿAmr said, “O Messenger of Allah, I own riding animals that I tend; I travel with them and rent them out, and at times this month—meaning Ramadan—coincides with me while I have the ability to fast, and I find it easier to fast than to postpone it and have it remain as a debt upon me.” He replied, “Whichever of those you wish, O Hamzah.”

Hadith 2
On the authority of Anas ibn Mālik (Allah be pleased with him): “We used to travel with the Messenger of Allah ﷺ, and the one who was fasting did not criticise the one who had broken his fast, nor did the one who had broken his fast criticise the one who was fasting.”

Overall meaning
When the Companions travelled with the Prophet ﷺ, some of them broke their fast while others continued to fast, and the Prophet ﷺ approved both courses. Fasting is the default rule, whereas breaking the fast is a concession; there is no blame for foregoing a concession, so they did not censure one another for fasting or for breaking the fast.

Points derived from the ḥadīth
1- The permissibility of breaking the fast while traveling.
2- The Prophet’s approval of his Companions both fasting and breaking the fast during travel shows that either option is lawful.