What is Sikhism’s attitude toward other faiths?

Instead of the undersigned saying anything about Sikhism, please be kind to read the opinion of renowned scholars, philosophers and writers according to whom Guru Granth Sahib is a secular, modern and universal scripture and teaches oneness of entire humanity:-

I have studied the scriptures of the great religions, but I do not find elsewhere the same power of appeal to the heart and mind as I find here in these volumes. They are compact inspite of their length and are a revelation of the vast reach of the human heart, varying from the most noble concept of God to the recognition and indeed the insistence upon the practical needs of human body. There is something strangely modern about these scriptures and this puzzled me until I learned that they are in fact comparatively modern, compiled as late as the 16th century when explorers were beginning to discover that the globe, upon which we all live, is a single entity divided only by arbitrary lines of our own making. Perhaps this sense of unity is the source of power I find in these volumes. They speak to person of any religion or of none. They speak for the human heart and the searching mind.
-Mrs. Pearl S. Buck, Noble laureate

Sikhism is a Universal world faith, has message for all men. This is simply illustrated in the writings of the Gurus. Sikhs must cease to think of their Faith as just another good religion and must begin to think in terms of Sikhism being the religion for this New Age… The religion preached by Guru Nanak is the faith of the New Age. It completely supplants and fulfills all the former dispensations of older religions… Books must be written proving this. The other religions contain the truth but Sikhism contains the fullness of truth… Guru Granth Sahib of all the world religious scriptures, alone states that there are innumerable worlds and universes other than our own. The previous scriptures were all concerned only with this world and its spiritual counterpart. To imply that they spoke of other worlds as does the Guru Granth Sahib is to stretch their obvious meanings out of context. The Sikh religion is truly the answer to the problems of modern man.
-Prof. H. L. Bradshaw

The religion of the Guru Granth is a universal and practical religion… Due to ancient prejudices of the Sikhs it could not spread in the world. The world today needs its message of peace and love.
-Archer

Mankind’s religious future may be obscure; yet one thing can be foreseen. The living higher religions are going to influence each other more than ever before, in the days of increasing communications between all parts of the world and branches of human race. In this coming religious debate, the Sikh religion and its scripture, Guru Granth, will have something special of value to say to the rest of the world.
-Arnold Toynbee

Pure Sikhism (as enshrined in Guru Granth) is far above dependence on Hindu rituals and is capable of distinct position so long as Sikhs maintain their distinctiveness. The religion is also one which could appeal to the occidental mind. It is essentially a practical religion. If judged from the pragmatical stand point which is a favourite point of view in some quarters, it would rank almost first in the world. Of no other religion can it be said that it has made a nation in so short a time. The religion of the Sikhs is one of the most interesting at present existing in India, possibly indeed in the whole world.
-Dorothy Field

For Nanak there was no such thing as a God for the Hindus, a god for the Muhammadans, and a god or gods for the outer heathen. For him there was but one God, not in the likeness of man, like Raman, not a creature of attributes and passions, like the Allah of Muhammad; but one sole, indivisible, self-existent, incomprehensible, timeless, all pervading – to be named, but otherwise indescribable and altogether lovely. Such was Nanak’s idea of the Creator and Sustainer of the phenomenal world, and it was a conception which at once abrogated all petty distinctions of creed, and sect, and dogma, and ceremony. The realisation of such God shatters the sophistries of the theologian and the quibblings of the dialecticians. It clears the brow from the gloom of abstruse ponderings over trifles and leaves the heart free for the exercise of human sympathies.
-Frederic Pincot, British Scholar

The Sikh religion differs as regards the authenticity of its dogmas from other great theological systems. Many of the great teachers the world has known have not left a line of their own composition, and we only know what they taught through tradition or second hand information. We know the teachings of Socrates only through the writings of Plato and Xenophan. Buddha has left no written memorials of his teachings. Kung-fu-zu, known to European as Confucius left no documents in which he detailed the principles of his moral and social system. The Founder of Christianity did not reduce his doctrines to writing and for them we are obliged to trust to the Gospels according to Matthew, Mark, Luke and John. The Arabian Prophet did not himself reduce to writing the chapters of the Quran. They were written or complied by his adherents and followers. But the compositions of the Sikh Gurus are preserved, and we know at firsthand what they taught. They employed the vehicle of verse, which is generally unalterable by copyists, and we even become in time familiar with their different styles. No spurious compositions or extraneous dogmas can, therefore, be represented as theirs… As we shall see hereafter, it would be difficult to point to a religion of greater originality or to a more comprehensive ethical system.
-Max Arthur Macauliffe, British Historian

In Brahmanical Hinduism, Buddhism and Jainism generations of teachers and commentators gave new shapes of religions and philosophical doctrines and sometimes changed them beyond recognition. The six schools of Hindu philosophy branched of into different groups of thinkers. The same process divided Jains and Buddhists into different and sometimes warring sects. The history of Islam as also of Christianity presents the same phenomenon of doctrinal disintegration. But Sikhism never succumbed to warring commentators; it preserved intact the heritage which Guru Nanak had left for it. None but a great and far-sighted founder can formulate doctrines capable of surviving the shocks of political and social revolutions for centuries… His humanity is transparent in his verses…
The story of Guru Nanak’s life and achievement has no parallel in the annals of this ancient land. It is not enough to call him the greatest of the sons of Punjab. He must be counted among the greatest of the sons of India. He was the founder of the last of the greatest religions of the world. He planted a poetical sapling which has blossomed into one of the great literatures of India. He laid the foundation of brotherhood which has enriched our national heritage by struggle against religious intolerance, social injustice and denial of political freedom. History must pay homage to one who – in serving God – served his country so well.
-Anil Chandra Banerjee, Professor of Guru Nanak Chair, Yadavpur University, West Bengal.

The more I dug into the pages of Guru Granth the more I fell in love with them… It is enough for us to take as it comes to us, to hear the lovely music in the truths he sang, to try to live the life of inspired service and practical devotion which he taught. For these things the world will always be in debt to Guru Nanak and to those through whom he spoke in the succeeding generations.
-Duncan Greenless, Theosophist from U.S.A.
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