Everything is stated there, what is Caitanya. Will everyone be able to understand it? That is the proof that he's not graduate. If he is graduate, then he should understand. Therefore it is postgraduate.
Kulādri: One must understand Bhagavad-gītā before Śrīmad-Bhāgavatam?
Prabhupāda: Yes. It is stated there yad advaitaṁ brahma upaniṣadi. That means he must understand the Upaniṣads. He must understand what is Brahman. So without understanding this, how he can understand Caitanya-caritāmṛta? It will be explained there, but the fact is this. What is that? Is there any explanation?
Puṣṭa Kṛṣṇa: No, there's no purport to this verse.
Prabhupāda: So further on there is explanation. Find out that.
Devotee (2): Śrīla Prabhupāda? How does one know when he has the understanding of the Bhagavad-gītā?
Prabhupāda: What does he say? Answer him.
Puṣṭa Kṛṣṇa: What did you say?
Devotee (2): How does one know when he has the understanding of Bhagavad-gītā?
Dhṛṣṭadyumna: One has understood Bhagavad-gītā who surrenders to Kṛṣṇa, because Kṛṣṇa says sarva-dharmān parityajya mām ekam śaraṇaṁ vraja (BG 18.66), that "The essence of all knowledge is to surrender unto Me, to give up all other duties." So one who takes that instruction as life and soul, he has understood Bhagavad-gītā. Is that all right?
Puṣṭa Kṛṣṇa: The same verse again in the Second Chapter."The compilers of the Upaniṣads speak very highly of the impersonal Brahman. The Upaniṣads, which are considered the most elevated portion of the Vedic literatures, are meant for persons who desire to get free from material association and who therefore approach a bona fide spiritual master for enlightenment. The prefix upa indicates that one must receive knowledge about the Absolute Truth from a spiritual master. One who has faith in his spiritual master actually receives transcendental instruction, and as his attachment for material life slackens, he is able to advance on the spiritual path. Knowledge of the transcendental science of the Upaniṣads..."
Prabhupāda: Where is that boy? You are hearing?
Devotee (2): Yes, Prabhupāda.