So Bhagavad-gītā is that: religion combined with philosophy. If you simply take philosophy, it is dry speculation, no juice. Carvita-carvaṇānām: "Chewing the chewed." There is no benefit. And if you take . . . simply take religion without basis of philosophy, then it is fanaticism. That's all. So both should be combined. Religion based on philosophy and logic, that is religion. So that combination is Bhagavad-gītā.
So here in the Seventh Chapter, beginning, opening chapter, it is said, bhagavān uvāca. You are searching after God. Now here is God Himself speaking. So recognized God by all sages: Vyāsadeva, Nārada, Asita, and later on by Rāmānujācārya, by Śaṅkarācārya, by Madhvācārya, by Viṣṇu Svāmī, by Caitanya Mahāprabhu, and then our Guru Mahārāja.
So our method is very simple, evaṁ paramparā-prāptam imaṁ rājarṣayo viduḥ (BG 4.2). So we accept this paramparā system. I may not know what is God, but because my predecessors, ācāryas, confirm it, the "Here is Bhagavān," we accept it. That's all. We save so much trouble by mental speculation. We accept the paramparā system, therefore. And we get the result. So that is the way.
Now here, not only the paramparā system . . . the paramparā system begins from Kṛṣṇa. As Kṛṣṇa says in the Fourth Chapter, imaṁ vivasvate yogaṁ proktavān aham avyayam (BG 4.1): "I spoke first to the sun god." It is not said: "First." Many times He has said to many predominating deities. But in this era . . . this is called the age of Vaivasvata Manu. There are fourteen Manus in one day of Brahmā. So Vaivasvata Manu is the eighth Manu.
That means we are passing through the midday of this era, manvantara. There is fourteen Manus in one day of Brahmā, and this era is called Vaivasvata Manu, because he is the son of Vivasvān. And that Vivasvān is given reference in the Fourth Chapter: imaṁ vivasvate yogaṁ proktavān aham avyayam (BG 4.1). So if you simply calculate the age of Manu it becomes forty millions of years.
So Bhagavad-gītā is not a new theses. It is coming from time immemorial. So Kṛṣṇa is the original preceptor. So here Kṛṣṇa again personally speaking, the authority, personally . . . out of compassion and friendship, love to Arjuna, He's speaking directly to Arjuna. And Arjuna understood Him the Supreme Personality of Godhead.