Ka’b reported: Allah Almighty said to Moses, upon him be peace, “O Moses, be soft in nature, for the most abhorred creation to me is one within whom is arrogance, in whose tongue is sharpness, and in whose heart is hardness. The most beloved character traits to me are mercy, compassion, kindness, and gentleness. O Moses, be merciful to my creation and I will have mercy on you. O Moses, I am merciful and I love those who are merciful. Blessed are those who are merciful. Again, blessed are those who are merciful. And again, blessed are those who are merciful.”
Source: Ḥilyat al-Awliyā’ 6/37
عَنْ كَعْبٍ قَالَ قال الله تعالى لموسى عليه السلام يَا مُوسَى كُنْ لَيِّنَ الْجَانِبِ فَإِنَّ أَبْغَضَ الْخَلْقِ إِلَيَّ الَّذِي فِي نَفْسِهِ كِبْرٌ وَفِي لِسَانِهِ جَفَاءٌ وَفِي قَلْبِهِ قَسْوَةٌ وَأَحَبُّ الْأَخْلَاقِ إِلَيَّ الرَّحْمَةُ وَالْعَطْفُ وَالرَّأْفَةُ وَالرِّقَّةُ يَا مُوسَى ارْحَمْ خَلْقِي أَرْحَمْكَ يَا مُوسَى أَنَا رَحِيمٌ أُحِبُّ الرُّحَمَاءَ يَا طُوبَى لِلرُّحَمَاءِ وَيَا طُوبَى لِلرُّحَمَاءِ وَيَا طُوبَى لِلرُّحَمَاءِ
6/37 حلية الأولياء وطبقات الأصفياء