One Bad Quality Can Spoil Numerous Good Ones
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.
Also read
Related sayings.
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.