وَعَنْهُ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «قَدْ أَفْلَحَ مَنْ أَخْلَصَ اللَّهُ قلبَه للإِيمان وجعلَ قلبَه سليما ولسانَه صَادِقا وَنَفْسَهُ مُطْمَئِنَّةً وَخَلِيقَتَهُ مُسْتَقِيمَةً وَجَعَلَ أُذُنَهُ مُسْتَمِعَةً وَعَيْنَهُ نَاظِرَةً فَأَمَّا الْأُذُنُ فَقَمِعٌ وَأَمَّا الْعَيْنُ فَمُقِرَّةٌ لِمَا يُوعَى الْقَلْبُ وَقَدْ أَفْلَحَ مَنْ جَعَلَ قَلْبَهُ وَاعِيًا» رَوَاهُ أَحْمَدُ وَالْبَيْهَقِيُّ فِي «شعب الْإِيمَان»
It is narrated from Abu Dharr (may Allah be pleased with him) that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Successful is the one whose heart Allah has made pure for faith, whose heart He has kept safe (from envy, malice, etc.), whose tongue He has made truthful, whose soul He has made content, whose nature He has made upright, whose ears He has made attentive to (the truth), and whose eyes He has made observant (of evidence). The ears are funnels for what the heart preserves, and the eyes are the place of settlement and stability. And successful is the one who has made his heart a guardian." Its chain is weak; narrated by Ahmad and Al-Bayhaqi in Shu'ab al-Iman.