Is it obligatory for a soldier with surplus provisions (a spare mount) to give it to another whose horse has been injured?
General Chapter
Al-Mughni
Book of Jihad
Primary text
It is recommended, but not obligatory, for a soldier who has an extra mount to carry another soldier whose own mount has been injured, provided the latter soldier is not in imminent danger of death. This opinion is explicitly stated by Ahmad.
Supporting text
If the afflicted soldier's life is genuinely feared to be lost without the spare mount, then the obligation arises for the possessor to offer his extra mount to save that life. This is analogous to the obligation to offer surplus food to one who is starving or to rescue someone from an enemy.