The ignorant man only says: "I am a great sinner." This is a serious mistake. Never for a moment think that you are a sinner. You are the most holy one, you are the ever-pure Atman. Sin cannot touch you. You are above vice and virtue, Dharma and Adharma. Punya and Papa are mental creations only. Sins are mistakes only. An ignorant Jiva commits these mistakes during the course of his journey in this world on account of Avidya or ignorance. Through mistakes he gains experiences and marches forward in his path of spirituality. Every mistake is your best teacher. One has to evolve through sins and mistakes. These mistakes are inevitable. Some people become a prey to thoughts of sin. They ever brood: "We are great sinners. We have committed many crimes." This is a great blunder.
Whenever thoughts of this nature worry you, you should think: 'I am doing Japa of Om. This will burn all old sinful actions. This will purify my mind. I am doing Tapas, fasting and charity. These are all great purifiers. I am becoming purer and purer. Nothing can affect me now. I am like the effulgent fire. I have become a holy person.' Assert, whenever such negative thoughts of sin trouble you: 'I am the Nitya Suddha, ever-pure Atman.'
Hear the words of assurance of Lord Krishna in the Gita: "Even if thou art the most sinful of all sinners, yet shall thou cross over all sin by the raft of wisdom. As the burning fire reduces fuel to ashes, O Arjuna, so doth the fire of wisdom reduce all action to ashes. Verily, there is no purifier in this world like wisdom; he that is perfected in Yoga finds it in the Self in due season." Ch. IV-36, 37, 38.
"Even if the most sinful worships Me with undivided heart, he too must be accounted righteous, for he hath rightly resolved. Speedily he becometh dutiful and goeth to eternal peace. O Kaunteya, know thou for certain that My devotee perisheth never. They who take refuge in Me, O Partha, though of the womb of sin, women, Vaishyas, even Sudras, they also tread the highest path. How much more easily, then, the holy Brahmins and devoted royal saints (attain the goal); having obtained this impermanent and unhappy world, do thou worship Me. Fix thy mind on Me, be devoted to Me, sacrifice unto Me, bow down to Me, having thus united thy whole self in Me, taking Me as the supreme goal, thou shalt come to Me." Ch. IX-30