by Abu Dawud.

Expedition of Sīf al-Baḥr:
Ibn ʿUyaynah narrated—through ʿAmr—from Jabir—that the Prophet ﷺ sent us out, three hundred mounted men, with Abu ʿUbaydah ibn al-Jarrah as our commander. We lay in wait for a caravan belonging to Quraysh, but hunger struck us so severely that we began eating the leaves of the desert acacia; for that reason we came to be called “the Leaf-Eating Army.”

He continued, “A man slaughtered three camels, then three more, and then another three, until Abu ʿUbaydah forbade him. Then the sea cast up for us a huge creature called al-ʿanbar. We ate from it for half a month and used its fat as ointment until our bodies recovered and regained strength. Abu ʿUbaydah took one of its ribs, set the tallest man in the army on the tallest camel, and the man rode beneath that rib without touching it.” Agreed upon (recorded by both al-Bukhari and Muslim).

Al-Bukhari adds in the version of ʿAmr from Jabir: “A man among the company slaughtered three camels, then another three, and yet another three, after which Abu ʿUbaydah stopped him.”

ʿAmr would also say: “Abu Ṣāliḥ told us that Qays ibn Saʿd said to his father, ‘I was with the army when they became hungry.’ His father said, ‘Slaughter,’ so I slaughtered. They hungered again, and he said, ‘Slaughter,’ so I slaughtered. When they grew hungry a third time he said, ‘Slaughter,’ but then I was forbidden.”