Mm...let me make my views as they stand at present as clear as possible on this matter.
I do not think that the Gurus had the same 'soul'. I do not think that the Gurus were any more 'divine' than you or I (i.e. we are
all divine, because we are all a part of God/the Cosmos/the Universe, as per the writings of
gurbani). I also think that
believing something as Paganistic/dietic and mystical as this would be a direct betrayal of the Gurus' teachings.
It is this 'Brahminical' thinking - applied to the Sikkh faith - that will be its ultimate demise.
You see, once you start believing that any man who is made of clay is somehow more 'God-like' than any other man of clay, you instantly instill a culture of hierarchical division. The Tenth Master often said that a gurudwara should never be erected in his name, because the only entity to be recognised is the One God (through whom all men, animals, plants, stars and planets exist as one unified entity) was the One God ("
ik onkaar" is the only concept in Sikkhism...that's why it's so simple...it's designed around an all-unifying singularity that requires no priests, no statues, no rituals, no saints, no prophets, no messiahs,
nothing in order to be reached...everyone is in touch with God / the Universe in every minute of their life, even if they don't consciously know it). When Guru Nanak died, the location of his death bed was built over in order to prevent ritualized worship to...nothing.
Guru Nanak was essentially a man who travelled the world looking for answers and testing out his theories. He came to the conclusion that only one God existed, and that all men were equal under him, and that all men had an innate access to him that didn't require any third parties or strange witchcraft.
He then passed on the core of his teachings to Guru Angad Dev (Guru Nanak used "
angad" as a term of affection, meaning "part of me"...aw, sweet?
), who actually retreated into the caves after Guru Nanak's death with a combination of grief upon the death of his mentor and a sense of burden at the prospect of having to follow up such a great man as a philosophical leader (again, this whole thing begs the question as to how they could possibly be 'one soul'...).
But Angad eventually rose to the challenge, and wonderfully so. He stressed the importance of
seva (the concept of selfless service to your fellow humans), the importance to submit to the Cosmic Will and not become frustrated with what you perceive to be negative events in life (e.g. death, monetary losses, etc), as well as the outright disapproval of being overly showy and dishonest. He also standardise the
gurmukhi script to aid its reading.
Guru Arjan Dev JiThe most noteworthy additions and alterations to the scriptures came when - the Fifth Master - actually rewrote some of Guru Nanak's writings, including the all-important
mool mantra (again, if there is one consciousness, then why is there a need to ammend previous writings? It's not like the Truth has changed).
Guru Gobind Singh Ji's creation of the Khalsa knights was a necessity of the time, and was a warrior group based on his own idealised image of a spiritual warrior; a turban-bearing, sword-wielding soldier who was in love with the essence of steel and what it brought in terms of the power to do righteous deeds in the face of inhuman opponents.
I've never doubted Guru Gobind Singh Ji's actions or methods even once. I believe that the Tenth Master did what he had to do. And did it exceedingly well: UNESCO recognises the acts of Khalsa warriors on the same level as those of the Spartan warriors of ancient Greece.
However, just as the situation had changed between the time of Guru Nanak and Guru Gobind, so too has the time changed between Guru Gobind and today's world. Moreso, in fact.
My proposition is that Sikkhism - a faith that believes in the Will of God (e.g. evolution and change) - should be able to...well...evolve and change.
What form that change takes is not something I want to discuss, but I'll leave it to you all to decide.
