One may ask that if Caitanya Mahaprabhu is Krsna Himself, then why did He need a spiritual master? Of course He did not need a spiritual master, but because He was playing the role of acarya (one who teaches by example), He accepted a spiritual master. Even Krsna himself accepted a spiritual master, for that is the system.
In this way the Lord sets the example for men. We should not think, however, that the Lord takes a spiritual master because He is in want of knowledge. He is simply stressing the importance of accepting the disciplic succession. The knowledge of that disciplic succession actually comes from the Lord Himself, and if the knowledge descends unbroken, it is perfect.
Although we may not be in touch with the original personality who first imparted the knowledge, we may receive the same knowledge through this process of transmission.
In Srimad-Bhagavatam, it is stated that Krsna, the Absolute Truth, the Personality of Godhead, transmitted transcendental knowledge into the heart Brahma. This, then , is one way knowledge is received-through the heart. Thus there are two processes by which one may receive knowledge: One depends upon the Supreme Personality of Godhead, who is situated as the Supersoul within the heart of all living entities, and the other depends upon the guru or spiritual master, who is an expansion of Krsna.
Thus Krsna transmits information both from within and from without. We simply have to receive it. If knowledge is received in this way, it doesn't matter whether it is inconceivable or not.
In Srimad-Bhagavatam there is a great deal of information given about the Vaikuntha planetary systems which are beyond the material universe.
Similarly, a great deal of inconceivable information through experimental knowledge is not possible. The knowledge simply has to be accepted. According to the Vedic method, sabda, or transcendental sound, is rearded as evidence. Sound is very important in Vedic understanding, for, if it is pure, it is accepted as authoritative.
Even in the material world we accept a great deal of information which is sent thousands of miles by telephone or radio. In this way we also accept sound as evidence in our daily lives.
Although we cannot see the informant, we accept his information as valid on the basis of sound. Sound vibration then is very important in the transmission of Vedic knowledge.
The Vedas inform us that beyond this cosmic manifestation there are extensive planets and the spiritual sky. This material manifestation is regarded as only a small portion of the total creation. The material manifestation includes not only this universe but innumerable others as well, but all the material universe combined comprise only one fraction of the total creation.
The majority of the creation is situated in the spiritual sky. In that sky innumerable planets float, and these are called Vaikunthalokas. In every Vaikunthaloka Narayana presides in the form of His four-armed expansions: Sankarsana, Pradhyumna, Aniruddha and Vasudeva.
As stated before, the material universe are manifestated by the Lord in the form of Maha-Visnu. Just as a husband and wife combine to beget offspring, the Maha-Visnu combines with His wife Maya, or material nature. This is also confirmed in the Bhagavad-gita where Krsna states:
sarva-yonisu kaunteya
murtayah sambhavanti yah
tasam brahma mahad yomir
aham bija-pradah pita
"It should be understood that all species of life, O son of Kunti, are made possible by birth in this material nature, and that I am the seed-giving father."(Bg. 14.4)
Visnu impregnated Maya or material nature simply by glancing at her. This is the spiritual method. Materially we are limited to impregnate by only one particular part of our body, but the Supreme Lord, Krsna or Maha-Visnu, can impregnate any part by any part. Simply by glancing the Lord can conceive countless living entities in the womb of material nature.
The Brahma-samhita also confirms that the spiritual body of the Supreme Lord is so powerful that any part of that body can perform the functions of any other part. We can only touch with our hands or skin, but Krsna can touch just by glancing. We can only see with our eyes, we cannot touch or smell with them. Krsna, however, can smell and also eat with His eyes. When foodstuffs are offered to Krsna we don't see Him eating, but He eats simply by glancing at the food.
We cannot imagine how things work in the spiritual world where everything is spiritual. It is not that Krsna does not eat or that we imagine that He eats; He actually eats, but His eating is different from ours. Our eating process will be similar to His when we are completely on the spiritual platform. On that platform every part of the body can act on behalf of any other part.
Visnu does not require anything in order to create. He does not require the goddess Laksmi in order to give birth to Brahma, for Brahma is born from a lotus flower which grows from the navel of Visnu. The goddess Laksmi sits at the feet of Visnu and serves Him.
In this material world sex is required to produce children, but in the spiritual world one can produce as many children as he likes without having to take help from his wife. Becuase we have no experience with spiritual energy, we think that Brahma's birth from the navel of Visnu is simply a fictional story. We are not aware that spiritual energy is so powerful that it can do anything and everything. Material energy is dependent on certain laws, but spiritual energy is fully independent.
Brahma is born from the navel of Garbhodakasayi Visnu, who is but a partial manifestation of the Maha-Visnu. Countless universe reside like seeds within the skin pores of the Maha-Visnu, and when He exhales, they all manifest. In the material world we have no experience of such a thing, but we do experience a perverted reflection in the phenomenon of perspiration. We cannot imagine, however, the suration of one breath of the Maha-Visnu, for within one breath all of the universes are created and annihilated.
Lord Brahma only lives for the duration of one breath, and according to our time scale 4320,000,000 years constitute only twelve hours of Brahma, and Brahma lives one hundred years of his years. Yet the whole like of Brahma is contained within one breath of the Maha-Visnu. Thus it is not possible for us to imagine the breathing power of the Supreme Lord. That Maha-Visnu is but a partial manifestation of Krsna.
Thus Krsnadasa Kaviraja Gosvami discusses Lord Caintanya Mahaprabhu as Sri Krsna Himself, the Supreme Personality of Godhead, and Lord Nityananda as Balarama, the first expansion of Krsna.
Advaitacarya, another principal disciple of Lord Caitanya Mahaprabhu's, is accepted as an expansion of the Maha-Visnu. Thus Advaitacarya is also the Lord, or, more precisely, and expansion of the Lord.
The word advaita means nondual, and his name is such because he is nondifferent from the Supreme Lord. He is also called acarya, teacher, because he disseminated Krsna consciousness. In this way he is just like Caitanya Mahaprabhu.
Although Caitanya is Sri Krsna Himself, He appears as a devotee to teach people in general how to love Krsna. Similarly, Advaitacarya appeared just to distribute the knowledge of Krsna consciousness. Thus he is also the Lord incarnated as a devotee.
Krsna is manifested in five different expansions, and He and all of His associates appear as devotees of the Supreme Lord in the form of Sri Krsna Caitanya, Nityananda, Advaitacarya, Gadadhara, Srivasa and others.
In all cases, Caitanya Mahaprabhu is the source of energy for all His devotees. Since this is the case, if we take shelter of Caitanya Mahaprabhu for the successful execution of Krsna consciousness, we are sure to make progress.
One devotional song by Narottama dasa Thakur states: "My dear Lord Caitanya, please have mercy upon me. There is no one who is as merciful as You. My plea is most urgent because Your mission is to deliver fallen souls, and no one is more fallen than I. I beg priority."