How to Look at Yourself and Others
It is reported that Bakr b. ʿAbdillāh Al-Muzanī – Allāh have mercy on him – said:
When you see someone older than you, say: he has preceded me in īmān and righteous actions so he is better than me; and when you see someone younger than you, say: I have preceded him in sinning and disobedience so he is better than me. And when you see your brothers honouring and revering you, say: this is a virtue they have attained; and when you see them falling short (in their treatment of you) say: this is [because of] a sin I committed.
Ibn Al-Jawzī, Ṣifatu Al-Ṣafwah, article 505: Bakr b. ʿAbdillāh Al-Muzanī.
Also read
Related sayings.
Faulting others for what they have repented from can reflect the sin on oneself.
Advice from Umar on what it means to be trustworthy, and avoiding anyone else.