We find, in  Bhagavad-gita , that the Lord, the entities, manifestation, time and action are completely explained. Taken together, this complete whole is called the Absolute Truth, Sri Krsna. The impersonal  Brahman  is also subordinate to the Complete Person. It is explicitly explained in the  Brahma-sutra  as being like the rays of the sun emanating from the sun disc.  Brahman  realization of the Absolute Truth is therefore incomplete. The Supreme Personality is above  Brahman . The Supreme Personality of Godhead is called  sac-cid-ananda .
Brahman  realization is realization of His sat, or eternal feature. Supersoul realization is realization of His  sac-cid  aspect—eternity and knowledge. But, realization of the Personality of Godhead, Sri Krsna, is realization of all features— sac-cid-ananda  —in full  vigraha , or form. The Lord has form. He is a transcendental person. This is confirmed in all Vedic literature. Just as we are persons, so is the ultimate truth. Realization of the Supreme Personality of Godhead is realization of all the features of the Absolute Truth. The complete whole personality must have all that we see and all that we do not see.
This phenomenal world is complete by itself. The twenty-four elements of which this manifestation is comprised are complete in this universe. No further outside energy is needed. When the time is come, the universe will be annihilated by the complete arrangement of the Complete. Small completes exist in the whole Complete. Incomplete knowledge results from misunderstanding of the complete Absolute Truth.
Bhagavad-gita  is complete. The Vedic knowledge is infallible. Here is an example of how the Hindus accept Vedic knowledge as complete: Cow dung is sacred according to Vedic scripture. If one touches the dung of an animal, he must bathe his whole body, and yet cow dung can purify an impure place or person, according to Vedic scripture. This seems contradictory, but because it is a Vedic injunction, we accept it, and, by that acceptance, we make no mistake. It has been found by modern chemists that cow dung is a composition of antiseptic properties.
Vedic knowledge is complete, and it is above all doubts or errors. And  Bhagavad-gita  is the essence of all Vedic knowledge. Vedic knowledge comes down from higher sources. It is not like our material independent research work, which is imperfect. We must receive this knowledge from the spiritual master, through the discipline succession, which began with the Lord Himself.