he asked Ibn Al-Musaiyab about fasting on a journey, so he narrated to him that Umar bin Al-Khattab said: "We fought in two battles along with the Messenger of Allah during Ramadan; the Day of Badr, and the Conquest (of Makkah), so we broke our fast during them."
Jami` at-Tirmidhi Book 8, Hadith 33
← Previous Hadith "We were on a journey with the Messenger of Allah. Some of us were fasting and some of us broke their fast. The one who broke their fast had no objection to the one who fasted, and the one who fasted had no objection to the one who broke his fast. They saw that whoever had the strength to fast then that was good, and whoever was weak, then breaking it was better."

Jami` at-Tirmidhi Book 8, Hadith 32 Next Hadith → "Some cavalry man of the Messenger of Allah came galloping upon us, so I came to the Messenger of Allah and found him having lunch. He said: "Come and eat." I said: 'I am fasting.' So he said: 'Come and I will narrate to you about the fast - or fasting. Indeed Allah Most High lifted (the fast and) half of the Salat from the traveler, and (He lifted) the fast - or fasting - from the pregnant person, or the breast-feeding person.' And by Allah! The Prophet said both of them or one of them. So woe to me! For I did not eat from the meal of the Prophet."

Jami` at-Tirmidhi Book 8, Hadith 34