Musnad Ahmad 33:414

Rawh narrated to us, Zakariya narrated to us, Abu al-Zubayr narrated to us, that he heard Jabir ibn Abdullah saying: We were with the Prophet, may God bless him and grant him peace, on a military expedition he undertook, and that was in Ramadan. A man from the companions of the Prophet, may God bless him and grant him peace, fasted, and he became severely weak, and thirst was about to kill him, and his camel began to go under the thorny trees. The Prophet, may God bless him and grant him peace, was informed about him, so he said: "Bring him to me." He was brought, and he said: "Are you not in the way of God, and with the Messenger of God, may God bless him and grant him peace? Break your fast." So he broke his fast.