Our only purpose is to present this Bhagavad-gītā As It Is in order to guide the conditioned student to the same purpose for which Kṛṣṇa descends to this planet once in a day of Brahmā, or every 8,600,000,000 years. This purpose is stated in Bhagavad-gītā, and we have to accept it as it is; otherwise there is no point in trying to understand the Bhagavad-gītā and its speaker, Lord Kṛṣṇa. Lord Kṛṣṇa first spoke Bhagavad-gītā to the sun-god some hundreds of millions of years ago. We have to accept this fact and thus understand the historical significance of Bhagavad-gītā, without misinterpretation, on the authority of Kṛṣṇa.