The rituals and sacrifices mentioned in the karma-kāṇḍa division of the Vedic literature are meant to encourage gradual development of self-realization. And the purpose of self-realization is clearly stated in the Fifteenth Chapter of the Bhagavad-gītā (15.15): the purpose of studying the Vedas is to know Lord Kṛṣṇa, the primeval cause of everything. So, self-realization means understanding Kṛṣṇa and one's eternal relationship with Him. The relationship of the living entities with Kṛṣṇa is also mentioned in the Fifteenth Chapter of Bhagavad-gītā (15.7). The living entities are parts and parcels of Kṛṣṇa; therefore, revival of Kṛṣṇa consciousness by the individual living entity is the highest perfectional stage of Vedic knowledge.
(Bhagavad-Gita--2:46---purport).

There are two classes of intelligent men. One is intelligent in material activities for sense gratification, and the other is introspective and awake to the cultivation of self-realization. Activities of the introspective sage, or thoughtful man, are night for persons materially absorbed. Materialistic persons remain asleep in such a night due to their ignorance ofself-realization. The introspective sage remains alert in the "night" of the materialistic men. The sage feels transcendental pleasure in the gradual advancement of spiritual culture, whereas the man in materialistic activities, being asleep to self-realization, dreams of varieties of sense pleasure, feeling sometimes happy and sometimes distressed in his sleeping condition. The introspective man is always indifferent to materialistic happiness and distress. He goes on with his self-realization activities undisturbed by material reactions.
(Bhagavad-Gita---2:69---purport).

If one wants to make steady progress on the path of self-realization, he must try to control the forces of the material senses. There are the forces of talk, forces of anger, forces of mind, forces of the stomach, forces of the genitals, and forces of the tongue. One who is able to control the forces of all these different senses, and the mind, is called gosvāmī, or svāmī. Such gosvāmīs live strictly controlled lives, and forgo altogether the forces of the senses. Material desires, when unsatiated, generate anger, and thus the mind, eyes and chest become agitated. Therefore, one must practice to control them before one gives up this material body. One who can do this is understood to be self-realized and is thus happy in the state of self-realization. It is the duty of the transcendentalist to try strenuously to control desire and anger.
(Bhagavad-Gita---5:23---purport).

Self-realization means knowing one's constitutional position in relationship to the Supreme. The individual soul is part and parcel of the Supreme, and his position is to render transcendental service to the Lord. This transcendental contact with the Supreme is called brahma-saṁsparśa.
(Bhagavad-Gita--6:28---purport).

One should give up all other processes of self-realization and simply execute devotional service in Kṛṣṇa consciousness. That will enable one to reach the highest perfection of life. There is no need for one to consider the sinful actions of his past life, because the Supreme Lord fully takes charge of him. Therefore one should not futilely try to deliver himself in spiritual realization. Let everyone take shelter of the supreme omnipotent Godhead, Kṛṣṇa. That is the highest perfection of life.
(Bhagavad-Gita--12:6-7---purport).

The symptoms of the self-realized person are given herein. The first symptom is that he is not illusioned by the false identification of the body with his true self. He knows perfectly well that he is not this body, but is the fragmental portion of the Supreme Personality of Godhead. He is therefore not joyful in achieving something, nor does he lament in losing anything which is related to his body. This steadiness of mind is called sthira-buddhi, or self-intelligence. He is therefore never bewildered by mistaking the gross body for the soul, nor does he accept the body as permanent and disregard the existence of the soul. This knowledge elevates him to the station of knowing the complete science of the Absolute Truth, namely Brahman, Paramātmā and Bhagavān. He thus knows his constitutional position perfectly well, without falsely trying to become one with the Supreme in all respects. This is called Brahman realization, or self-realization. Such steady consciousness is called Kṛṣṇa consciousness.
(Bhagavad-Gita--5:20---purport).