Hawzah News Agency – The commander of the faithful, Imam Ali peace be upon him says:
أحمَقُ النّاسِ مَن أنْكَر على غَيرِهِ رَذيلَةً وهُو مُقيمٌ علَيها.
'The most foolish of people is he who rebukes others for their vices while he possesses the same.'
Source: Ghurar al-Hikam, no. 3343