Amīr al-mu’minīn's encounter with Ḥarb ash-Shibāmi
Nahj al-Balāgha|Volume 1|Book 3|Chapter 322
وَأَقْبَلَ حَرْبٌ يَمْشِي مَعَهُ، وَهُوَ (عليه السلام) رَاكِبٌ. فَقَالَ (عليه السلام) لَهُ: ارْجِعْ، فَإِنَّ مَشْيَ مِثْلِكَ مَعَ مِثْلِي فِتْنَةٌ لِلْوَالِي، وَمَذَلَّةٌ لِلْمُؤْمِنِ.
Ḥarb began to walk with him while Amīr al-mu’minīn was on horseback, so Amīr al-mu’minīn, peace be upon him, said to him: Get back because the walking of a man like you with one like me is mischief for the ruler and disgrace for the believer.