Among the perils of conceit is that instead of one seeing his faults and shortcomings, he becomes too blind to see these, so he does not examine his deeds, nor does he ascertain his acts of worship. If the nafs and Satan find their ways to him through other venues such as pretension and others, one may treat himself before it is too late. But due to this disease [of conceit], one may not correct the conditions required for the soundness of his rituals and acts of adoration, so his good deeds and worship become void even according to obvious religious laws and according to the verdicts of scholars of the Sharī`a.
But since he admires his good deeds, he does not look for such verdicts so he may apply them to the sacred rites. The poor man finds himself in a situation in which the adoration of as long as fifty years of his lifespan is void and was not correct even in a way where he can repeat them and make up for them. What a fault is greater than one being unaware of seeing his faults?! The Prophet (ص) says, "Suffices one for a fault is that he sees people's faults while being too blind to see his own." Imām Ali bin Muhammad al-Hadi (ع) has said, "One who is pleased with himself will find many who are displeased with him."
Lord! Enable us to see our faults so such vision may be one of the marks of Your love for us. He, peace be with him, has said, "If Allāh loves a servant, He enables him to see his own faults."