Sayyiduna Ali (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) intended to send me to Yemen, so I said: O Messenger of Allah! You are sending me to a people who are older than me, and I am young in age; I cannot judge properly. The Prophet (peace and blessings be upon him) placed his blessed hand on my chest and prayed: «اَللّٰهُمَّ ثَبِّتْ لِسَانَهُ وَاهْدِ قَلْبَهُ» "O Allah! Make his tongue firm and guide his heart." O Ali! When two parties come to you, do not judge by listening to only one of them, but listen to both sides; in this way, it will be easier for you to judge." Sayyiduna Ali (may Allah be pleased with him) says that after that, I never faced any difficulty in making a judgment.