It is reported that ʿUmar b. Al-Khaṭṭāb – Allāh be pleased with him – said to a young man while exhorting him:
A man might have ten qualities, nine of them good and one bad, but the nine good ones can be spoiled by the one bad quality. Beware of the slips and faults of youth.
ʿAbd Al-Razzāq Al-Ṣanʿānī, Al-Muṣannaf 8240.
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It is reported that ‘Umar b. Al-Khattāb – Allāh be pleased with him – said: Whoever exposes himself to suspicion, let him blame only himself for whoever suspects him. He who covers his secret is in a position to choose [to correct himself]. Assume the best about your brother until what comes to you from […]
Advice from Umar on what it means to be trustworthy, and avoiding anyone else.
Two qualities of a real man, not the one babbles on about himself.