وَإِذَا عَطِبَتِ الْبَدَنَةُ فِي الطَّرِيقِ فَإِنْ كَانَتْ تَطَوُّعًا نَحَرَهَا، وَصَبَغَ نَعْلَهَا بِدَمِهَا، وَضَرَبَ بِهَا صَفْحَتَهَا.
Translation: If a voluntary sacrificial camel fails on the journey, he slaughters it and marks the animal with the blood-stained shoe attached to its garland.
Na‘l refers to a shoe tied to the traditional garland identifying a hady animal; ṣafḥah is its side.
The marking was a historical means of identifying a failed voluntary offering for the poor. It is not a substitute for lawful modern animal handling or official sacrificial arrangements.
This is a special emergency case involving an animal that cannot reach its destination; it does not permit routine slaughter of sound hady outside the Haram.