عَنْ أَبِي هُرَيْرَةَ أَنَّ رَجُلًا شَكَا إِلَى رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَسْوَةَ قَلْبِهِ فَقَالَ لَهُ "إِنْ أَرَدْتَ تَلْيِينَ قَلْبِكَ فَأَطْعِمْ الْمِسْكِينَ وَامْسَحْ رَأْسَ الْيَتِيمِ"
Abu Huraira reported: A man came to the Messenger of Allah, peace and blessings be upon him, and he complained about the hardness of his heart. The Prophet said, “If you want to soften your heart, feed the poor and pat the head of the orphan.”
Source: Musnad Aḥmad 7576