Abu Saeed Khudri reported,

The Messenger of Allah ﷺ came upon a stream from the sky while the people were fasting on a hot day, traveling on foot, and the Prophet of Allah was riding his mule. He said, "Drink, people."But they refused.He said, "I am not like you. I am the most at ease among you, for I am riding."Still they refused. So the Messenger of Allah ﷺ swung his thigh over and dismounted, then drank, and the people drank as well, though he had not wanted to drink.

Azami 4598

Sahih

عن أبي سعيد، قال

أتى رسول الله ﷺ على نهر من السماء، والناس صيام في يوم صائف مشاة، ونبي الله على بغلة له، فقال: اشربوا أيها الناس. قال: فأبوا. قال: إني لست مثلكم إني أيسركم، إني راكبفأبوا. فثنى رسول الله ﷺ فخذه فنزل فشرب، وشرب الناس، وما كان يريد أن يشرب.

الأعظمي 4598صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Fasting
Chapter
What is permitted and what is not permitted for the fasting person
Section
It is permissible for the traveler to break the fast after beginning to fast without an excuse
Numbering
Jami al-Kamil 4598 (2nd edition)
Azami 4598