On the day of the battle of Tabuk, the Muslims were hard pressed by hunger and they asked Messenger of Allah (ﷺ): "O Messenger of Allah, grant us permission to slaughter our camels to eat and use their fat". He (ﷺ) accorded permission. On this 'Umar (May Allah be pleased with him) came and said: "O Messenger of Allah, if it is done, we shall suffer from lack of transportation. I suggest you pool together whatever has been left and supplicate Allah to bless it." Allah will bestow His Blessing upon it. Messenger of Allah (ﷺ) agreed and called for leather mat and had it spread out, and asked people to bring the provisions left over. They started doing it. One brought a handful of corn, another brought a handful of dates, a third brought a piece of bread; thus some provisions were collected on the mat. Messenger of Allah (ﷺ) invoked blessings, and then said, "Now take it up in your vessels". Everyone filled his vessel with food, so that there was not left a single empty vessel in the whole camp. All of them ate to their fill and there was still some left over. Messenger of Allah (ﷺ) said, "Any slave who meets Allah, testifying there is no true god except Allah, and that I am His Messenger, without entertaining any doubt about these (two fundamentals), will not be banished from entering Jannah."

[Muslim].