Al-Kāfi - Volume 6 > The Relation between a Stumper and the Rider
Hadith #4

عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ عَلِيِّ بْنِ رِئَابٍ قَالَ قَالَ أَبُو عَبْدِ اللَّهِ ( عليه السلام ) اشْتَرِ دَابَّةً فَإِنَّ مَنْفَعَتَهَا لَكَ وَ رِزْقَهَا عَلَى اللَّهِ عَزَّ وَ جَلَّ .

4. Ali ibn Ibrahim has narrated from his father from ibn abu ‘Umayr from Ali ibn Ri’ab who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘Buy a stumper; its benefit is for you and its sustenance with Allah, most Majestic, most Glorious.’”