In their book Vaishnavism and Nam-Bhajan, two great Gaudiya Vaishnava acaryas, Srila Thakur Bhaktivinoda and Srila Bhaktisiddhanta Sarasvati Thakur, give an astounding definition of "Vaishnava".
" The word 'Vaishnavism' indicates the normal, eternal and natural condition, functions and devotional characteristics of all individual souls in relation to Vishnu, the Supreme, the All-pervading Soul.
"But an unnatural, unpleasant and regrettable sense has been attributed to the word, making one understand by the word 'Vaishnava' (literally a pure and selfless worshipper of Vishnu) a human form with twelve peculiar signs (Tilak) and dress on, worshipping many gods under the garb of a particular God and hating any other human form who marks himself with different signs, puts on a different dress and worships a different God in a different way and designated by the words 'Saiva', 'Shakta', 'Ganapatya', 'Jaina', 'Buddhist', 'Muhammadan', 'Christian', etc.
"The word 'Vaishnava' literally and naturally means one who worships Vishnu out of pure love, expecting nothing from Him in return.
"Vishnu, the Supreme, All-pervading Soul, gives life and meaning to all that is. He is the highest, unchallengeable Truth, devoid of illusion everywhere and existing through eternity. He is sat (ever existing), cit (all-knowing), ananda (ever-blissful) and fully free.
"He is in jivas and jivas are in Him, as are the rays in the glowing sun and the particles of water in the vast rolling ocean. As nothing but heat and light of the sun, and coldness and liquidity etc. of the sea is found in the constituents of the rays and the particles of water respectively, so nothing but sat, cit or free will, and ananda is found in the jiva.
"The ingredients and attributes of the whole must remain in the part in a smaller degree. So the part is identical with the whole when taken qualitatively and different when taken quantitatively.
"As the service of the master is the fundamental function of the servant, so the service of Vishnu is natural and inherent in the jiva; it is called Vaishnavata or Vaishnavism, and every jiva is a Vaishnava. As a person possessing immense riches is called a miser if he does not display and make proper use of them, so jivas when they do not display Vaishnavata are called non-Vaishnavas or a-Vaishnavas, though in reality they are so."
From The Bhagavata, we read on page 18:
"The superiority of Bhagavan consists in the uniting of all sorts of theistic worship into one excellent principle in human nature, which passes by the name 'bhakti'. This word has no equivalent in the English language. Piety, devotion, resignation, and spiritual love unalloyed with any sort of petition except in the way of repentance, compose the highest principle of bhakti. The Bhagavata tells us to worship God in that great and invaluable principle which is infinitely superior to human knowledge and the principle of yoga."
On page 32:
"The spirit of the text [of the Srimad Bhagavatam] goes far to honour all great reformers and teachers who lived and will live in other countries. . . . Vaishnavism is the Absolute Love binding all men together into the infinite unconditioned and absolute God. . . . Plato looked at the peak of the spiritual question from the West and Vyasa made the observation from the East."
Regarding divisive sectarianism or the 'party spirit,' he also wrote in The Bhagavata:
"The true critic is a generous judge, void of prejudices and party spirit. One who is at heart the follower of Muhammad will certainly find the doctrines of the New Testament to be a forgery by the fallen angel. A Trinitarian Christian, on the other hand, will denounce the precepts of Muhammad as those of an ambitious reformer.
"The critic should be of the same disposition of mind as the author whose merits he is required to judge. Thoughts have different ways. One who is trained up in the thoughts of the Unitarian Society or of the Vedanta of the Benares school, will scarcely find any piety in the faith of the Vaishnavas. An ignorant Vaishnava, on the other hand, whose business it is to beg from door to door in the name of Nityananda, will find no piety in the Christians. This is because the Vaishnava does not think in the way in which the Christian thinks of his own religion.
"It may be that both the Christian and the Vaishnava will utter the same sentiment, but they will never stop their fight with each other only because they have arrived at their common conclusion by different ways of thought."
Srila Bhaktivinoda has lamented, "Oh! What a trouble it is to get rid of prejudices gathered in unripe years!"
In these words of two of our great Vaishnava acaryas, we see a concise description of the prejudice that continues to divide us as jivas and Vaishnavas, and of the transcendent love that can unite us as jivas and Vaishnavas in a generous spirit of non-sectarian pure bhakti.
External matters of race, class, dress, lineage markings, language, ritual differences, etc. are not significant when compared to the fact that we are all jivas -- 'children' of the same God. What is spiritually significant however, is our fundamental difference in devotion as a matter of rasa, or our natural taste for specific flavors (rasas) of divine love, in our personal relationships with God. While these various flavors and their tasteful combinations may predominate in various religions, and in different lineages of the same religion, they should never cause so-called 'spiritual pride' or prejudice, and hostility towards other devotees.
The Sankirtan movement of Sri Sri Gaura-Nitai was not restricted to those who worshipped Sri Caitanya or Sri Sri Radha-Krishna in a single lineage. Nor was it meant simply to unite the various factions of Madhva-related Vaishnavas, or even only the 'Hindu' Vaishnavas. The Sankirtan movement of Sri Sri Gaura-Nitai's time embraced, and was embraced by Saivites, Muslims and Buddhists.
Nama-bhajan -- or the simplest form of the heartfelt invocation of God by His Holy Name -- is common to all great bhakti traditions. Vaishnavas, Catholics, Jews, Muslims, Pure Land Buddhists, Saivites, members of many Indigenous traditions and other devotees of the Supreme Lord, since ancient times and to the present, practiced and still practice Nama-bhajan.
Sri Krishna has hundreds and millions of holy names and there are no hard and fast rules for invoking Him. God delights to hear His name from our lips and to know that we desire His company within our hearts. To invoke God by His name is to acknowledge His Being and to re-establish our (forgotten) unique personal relationship with Him. The pleasure that the Absolute experiences, when the finite jivas acknowledge Him, is gifted back to the jivas unlimitedly as the jivas hear God's own loving reply in the depths of their soul.
May Sri Nityananda Balarama be the constant inspiration of all Gaudiya Vaishnavas as they prosecute the non-sectarian Sankirtan movement of Sri Chaitanya Mahaprabhu for the benefit of all.