Goddess Sarasvati explained that "O Sage! the person impure physically and mentally both viz who has unwashed hands, denied of conscious on Vedas and inexperienced to dealing with the essence of Vedas is unentitled to offer the oblation in the fire. The Gods are always interested to know the deposition of others, they prefer sanctity and this is the reason they do not accept the oblations offered by a man without obeisance.
सरस्वत्युवाच ब्रह्मविज्जुहुयानाविपश्चित्। बुभुत्सवः शुचिकामा हि देवा नाश्रद्दधानाद्धि हविर्जुषन्ति॥