Explanation:
In the Gita, God has mentioned clearly about the medium for His direct entry to be the human body alone (Manushim tanumashritam). He did not mention other living forms like a fish etc. The liberated souls also preach and this possibility is also clearly mentioned (Jnaaninastattva darshinah—Gita). The Lord also said that there is no difference between Himself and such a liberated soul (Jnaanitvaatmaiva—Gita). He also stated that such liberated souls involved in preaching are very dear to Him (Priyohi… —Gita), since they are His best devotees (Bhaktaastetiva…—Gita). The Lord identifies Himself with them in all aspects and He did not enter directly since there was no need for Him to enter directly in order to preach to the lower levels of humanity. Except for this one point of the absence of need for direct entry, God treats such liberated souls as full representatives of Himself.
Note:
What is the difference between God directly entering and His power entering?
God’s power is unimaginable, God is also unimaginable. But God is the source of the unimaginable power. The source and power are different. Suppose you wind a copper wire (like a spring), and when the wire is unwound, kinetic energy is produced (it springs back). The work of winding came from you. The kinetic energy supplied by you has reappeared during the unwinding process of the wire. Similarly, if you rub your hands together, heat will be produced. The generated heat is your work alone. Thus you can introduce your power in the form of work into something and that thing can regenerate your power as work again. In the same way God can introduce His power into something and that power can be regenerated for doing some divine work. This is different from you yourself entering into a house and staying in that house.
You are speaking directly to somebody. Here there is no mediating working element. You are directly doing the work. Is there a difference? There is a difference. You are talking and that talk is being recorded. In this case the intermediate recording cassette is there. You have introduced your voice into the cassette and that cassette is regenerating the voice. Instead when you talk directly, cassette is not there. There is a difference between you talking directly and the cassette talking. Suppose God wants to kill a demon, He can introduce His power into a human being or any living being and that being can kill the demon using that power. For such acts God need not directly enter. Suppose your cassette is playing some recorded lesson and somebody from the audience gets some doubts; can the cassette answer those doubts? Suppose you are teaching a class directly and somebody asks some doubts, can you not answer and clarify the doubt rightaway?
Thus, there is a difference between the knowledge, which is recorded in a cassette and sent through somebody and the knowledge directly preached by God. When a messenger is sent, he carries the message. A postman brings a letter to you, and while reading the letter you get a doubt, can the postman clarify? Suppose somebody is speaking to you over the telephone, you can ask your doubts and he can clarify. The messenger is different from God directly coming. Suppose God is in the messenger, then the messenger can clarify the doubts.
Especially in the case of knowledge, direct involvement is needed. Suppose some demon has to be killed, God can introduce the power into somebody and he can go kill the demon and come back. Suppose you are a teacher and you teach a topic to a student and ask the student to teach that topic to the rest of the class. When some questions arise in the class, the student will not be able to give an answer to that question. He may answer to a certain extent but he cannot answer to the full satisfaction of the class. So preaching knowledge is different from killing some demon. For preaching knowledge God has to come directly. For doing other things, God need not come directly; His power is sufficient. In the case of the Fish-Incarnation killing the demon to protect the Vedas God’s direct presence is not needed. He can introduce His power in to the Fish and the Fish can kill the demon. Suppose Krishna is sent as a messenger by God to this world and when He is preaching to Arjuna Arjuna asks some doubts. Krishna cannot answer the questions like God. In that case, Krishna has to raise His hands upwards and say “O Lord, Arjuna is asking this question. What is the answer for that?”! Then God has to speak to Krishna and Krishna has to repeat the answer to Arjuna. Instead of all this nonsense can God not directly enter into Krishna? Killing a demon is decided and it is a unidirectional work, but preaching knowledge is not a unidirectional work, it is a multidirectional (interactive) and creative work. So for the sake of preaching, God has to come directly. Even Satan can do miracles. Jesus was tested by Satan to produce bread from stones. Jesus said that you should not test God. So, performing miracles is a unidirectional power. But if Satan asks a question, then Jesus cannot answer it and again God has to give the answer.
In fact, God is pleased to come directly and preach. Instead of sending some messenger for preaching and when some question arises, the fellow coming back for an answer and going back to convey it to questioner, the Lord Himself can come down. Then all these difficulties are removed. Killing a demon is not thrilling, simply go and kill. It is unidirectional. God will get pleasure if God preaches directly. There is a thrill in preaching directly and clearing the doubts directly. God is entertained in such work. It is multi-directional (interactive) work and God enjoys it. Krishna is recognized as God only through Gita, not through the miracles that He performed. Even Satan can do miracles.
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