ajñaśh chāśhraddadhānaśh cha sanśhayātmā vinaśhyati
nāyaṁ loko ’sti na paro na sukhaṁ sanśhayātmanaḥ||40||

Meaning : Doubt and lack of faith lead to confusion and spiritual downfall. Without true knowledge and trust, a person cannot find peace or happiness, neither in this life nor beyond. Doubt is a major obstacle on the path to liberation.