Self-reflection and contentment in Islamic teachings
Nahj al-Balāgha|Volume 1|Book 3|Chapter 349
وَمَنْ نَظَرَ فِي عُيُوبِ النَّاسِ فَأَنْكَرَهَا ثُمَّ رَضِيَهَا لِنَفْسِهِ فذَاك الْأَحْمَقُ بِعَيْنِهِ.
He who observes the shortcomings of others and disapproves of them and then accepts them for himself is definitely a fool.