Sri Guru comes in many forms , we should note Prabhupada says in the Caitanya Caratamrita , Diksa Siksa no difference . Sometimes the Diksa is also the Siksa , meaning they can take a particular disciple where they are qualified to go , but generally in Gaudia Vaisnava history a Siksa Guru completes the task ..What is the task , from beginning to end ? It’s clearly laid out by Srila Rupa Goswami beginning with faith , association to hearing , chanting.

These stages are:
1. Shraddha — faith
2. Sadhu-sanga — association with devotees
3. Bhajana-kriya — trying to seriously take up the process of devotional service
4. Anartha-nivrtti — becoming free of all unwanted things
5. Nistha — steadiness in Krishna consciousness
6. Ruchi — a deep taste for Krishna consciousness
7. Asakti — attachment for Krishna
8. Bhava — ecstasy, the first rays of the sun of love for Krishna
9. Prema — pure love for Krishna

Included in the spiritual calculations in terms of further  advancements are .

Deep smaranam,  ( slight seeking )

Dharana ( holding Radha Krishna forms and lila in the mind )

Dhyana ( deeper meditations and details of lilas and aspirations of services)

Dhruvanasmrti (uninterrupted recollection and inner services)

These proccess bringing stages of Bhava and in some cases prema .

Further description are given on the deeper inner esoteric levels

Sneha , mana , pranaya , Raga, anuraga . Means , Lit heart,  familiarity of sulking , oneness of emotions , trancendental criticism and blame , newer and newer feelings of attraction.

So the point being , as to why there are Diksa and Siksa Gurus because there are many aspects to complete pure Krishna consciousness , obviously there is a vast range of spiritual consciousness developments,  and Krishna makes arrangements for the devotees as they qualify themselves,  and Sri Guru in their many forms will automatically appear , if you really want Krishna, He appears as specific Gurus.

No question of your Guru my Guru male Guru female Guru,  Guru is one , the external representative of Krishna and and also an intimate servant of Srimati Radharani in one way or another , some of the cowherd boys are also serving indirectly Srimati Radharani.

We should know of course the following verse applies,  there is no sentimentality involved but rather realised knowledge and application of Sastra.

tasmād guruṁ prapadyeta
jijñāsuḥ śreya uttamam
śābde pare ca niṣṇātaṁ
brahmaṇy upaśamāśrayam

Translation

Therefore, any person who seriously desires real happiness must seek a bona fide spiritual master and take shelter of him by initiation. The qualification of the bona fide guru is that he has realized the conclusions of the scriptures by deliberation and is able to convince others of these conclusions. Such great personalities, who have taken shelter of the Supreme Godhead, leaving aside all material considerations, should be understood to be bona fide spiritual masters.

More ..

How should institutions deal with a service of being Guru..
The best policy is to explain clearly and decisively what Gaudia Vaisnava Guru tattva is and leave it to individuals .
I think the reason for appointments in ISKCON are twofold
That many Gurus have appointed successors in traditional Vedic settings , but that was in the cases of a small localised villages and geographical areas .
I think when Prabhupada left the GBC thought it wise to protect devotees, because any Tom dick or Harry or even Gladys could have declared themselves Guru , it could have seriously broken ISKCON, but they went too extreme and became political and mundane in their calculations.
Srila BR Sridha Swami told them to ease off and allow a more educated spirit to develop and if a person found attraction spiritually in another person and they were somewhat qualified to allow more Gurus …Unfortunately the GBC at that time made BR Sridhar Swami their enemy for saying those things .
But eventually, through his advice through many discussions, the Guru reform movement came about .
Things are moving in the right direction, but more work needed , no need to legislate anymore , rather educate .about Diksa Siksa tattva ….let individuals make their own decisions, but if someone is a sentimentalist or does not know tattva , ISKCON could not really approve them as Guru .so some systems are needed for a large institutional spiritual organisations , and careful consideration is needed. No rubber stamping , but a general protection against clearly unqualified persons who are unable to understand the meanings of Sri Guru ..
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