Now, Lord Caitanya is explaining this system, different systems: ritualistic, philosophical, meditation, morality, all these in śāstra-kahe. The real Vedic instruction is . . . just like, what is Veda? Veda means the words of the Lord. That is Veda. Scripture means the words of the Lord. God says, "Let there be light." God says, "Let there be creation." These words are scripture. Now one who takes out . . . just like sound is transmitted from a certain place, and one who captures by the machine, he gets the information, similarly, Veda means instruction transmitted by the Supreme Lord, and there are capable personalities, just like Brahmā, that capture it, and that is distributed, either in writing or by tradition, by hearing. That is scripture. The words of God.
Now, here the Supreme Personality of Godhead, Kṛṣṇa, is personally speaking Bhagavad-gītā. Is it not Veda? That is Veda. That is real Veda. Sarva-upaniṣade. In the Gītā-māhātmya it is said, "This is the essence of all Veda." This is Vedānta. Simply by studying Bhagavad-gītā, one becomes a learned science in the science of God.
So śāstra-kahe. Śāstra-kahe. And what (is) that śāstra? The essence of all śāstra, the essence of all scripture, asks you to do—the śāstra says, the Lord says—sarva-dharmān parityajya mām ekaṁ śaraṇaṁ vraja (BG 18.66): "Give up everything. Just surrender unto Me." This is the most confidential part of knowledge. So "give up everything" means there are different processes, different processes: ritualistic processes, different religious processes, philosophical processes, meditation, so many. "Give up all. Simply surrender to Kṛṣṇa."
So Lord Caitanya is stressing on that point that, aiche śāstra kahe—karma, jñāna, yoga tyaji'. Karma. Karma means general activities on moral principle. That is called karma. Karma means, real karma means that you have to live, so you have to work. So work in such a way that you may not be entangled. Just like honest businessman, he works; he works according to the law. He does not play any blackmailing, and he pays the proper income tax to the government and the other taxes. He does nicely. This is called work, karma. You have to live. Without working you cannot live. But you work in such a way so that you may not be entangled. That is called work, karma yoga. Now, this work is not the solution of your human life. You can get some morsel of bread and eat and drink and sleep and just enjoy your wife and die like cats and dogs, that's all. And then you will take with you the result of your good work or bad work. That is karma. That is not solution.
Then the next stage is, above this karma, this ordinary, general people, there is a class, they are thinkers. They are thinkers: "Whether this is the solution of life?" So thinkers, some of them are dry thinkers. They have no knowledge, but they think only. They do not get the source of knowledge from higher authorities; they manufacture their own way. So apart from that, those who are bona fide thinkers, they are called jñānī. Jñānī means that this process of karma cannot make solution of life. They push some philosophical thesis that "This is the solution of life." They are called jñānī.