Ali and Umar were leaving from Tawaf when they saw a Bedouin with his mother. The Bedouin carried his mother on his back and was chanting:

"I am her mount which does not flee... Even if the caravans are terrified, I stay calm,

What she carried and nursed me for is greater,

Here I am, O Allah, here I am."

Ali then said: "O Abu Hafs (Umar), let us join the Tawaf; perhaps mercy will descend upon us and encompass us." So the Bedouin continued his walk with his mother, chanting:

"I am her mount which does not flee... Even if the caravans are terrified, I stay calm,

What she carried and nursed me for is greater,

Here I am, O Allah, here I am."

Ali responded to him by saying: "If you honor her, Allah is most grateful, rewarding you with more for the little."  

خَرَجَ عَلِىٌّ وَعُمَرُ مِنَ الطَّوافِ فَإِذَا هُمَا بِأَعْرَابِىٍّ مَعَهُ أُمٌّ لَهُ فَحَمَلَهَا عَلَى ظَهْرِهِ وَهُوَ يَرْتَجِزُ وَيَقُولُ:

أَنَا مَطِيَّتُهَا لَا أَنْفِرُ ... وَإِذَا الْركَابُ ذُعِرَتْ لَا أُذْعَرُ

وَمَا حَمَلَتْنِى وَأَرْضَعَتْنِى أَكْبَرُ

لَبَّيْكَ الَّلهُمَّ لَبَّيْكَ.

فَقَالَ عَلِىٌّ: مُرْيَا أَبَا حَفْص ادْخُلْ بِنَا الطَّوَافَ لَعَلَّ الرَّحْمَةَ تَنْزِلُ فَتَعُمَّنَا فَدَخَلَ يَطُوفُ بِهَا وَهُوَ يَقُولُ:

أَنَا مَطِيَّتُهَا لَا أَنْفِرُ ... وَإِذَا الْركَابُ ذُعِرَت لَا أُذْعَرُ

وَمَا حَمَلَتْنِى وَأَرْضَعَتْنِى أَكْبَرُ

لَبَّيْكَ الَّلهُمَّ لَبَّيْكَ

قَالَ: وَعَلِيٌّ يُجيبُهُ يَقُولُ: إِنْ تَبرَّهَا فَالله أَشْكَرُ، يُجْزِيكَ بِالْقَلِيلِ الأَكْثَر