All ācāryas— Rāmānujācārya, Madhvācārya, Viṣṇu, Nimbārka, and latest, Śrī Caitanya Mahāprabhu, and before that, other ācāryas like Vyāsadeva, Nārada, Asita, Devala, and before that, the original
ācārya , Lord Brahmā, Lord Śiva—everyone accepted Kṛṣṇa the Supreme Personality of Godhead.
We are searching after whether there is God or there is no God. If there is God, what is the nature? What is the form? Whether He is person or imperson? There are so many questions. And to solve all these questions, the God Himself descends and speaks about Himself, and that speaking is this Bhagavad-gītā.
God is speaking about Himself personally, personally present. So you can know Him, you can see Him, what He is, what is His function. Just to mitigate all our doubts, God is present here. And Kṛṣṇa says in