"Allah has turned in mercy to the Prophet, and to the Muhajirun and the Ansar who followed him in the hour of difficulty," meaning: at the time of hardship, "after the hearts of a party of them had well-nigh swerved," meaning: inclined away from the struggle (Jihad). Allah—Exalted and Majestic is He—protected them from that, so they proceeded with the Prophet (peace and blessings of Allah be upon him). Qatadah said: They suffered severe exhaustion in this expedition, to the extent that it reached us that two men would split a single date between them, and a group would take turns with a single date, one would suck on it, then drink water after it, and then the other would suck on it.
Surat al-Tawbah, from verse (118) to verse (119).