“If people but knew their own religion, how tolerant they would become, and how free from any grudge against the religion of others.”

Subaji Bapu, MataparIkshAsikshA, from his reply to John Muirs Matapariksha, Cited by R.F. Young and quoted from Goel, S. R. (2016). History of Hindu-Christian encounters, AD 304 to 1996. Chapter 10. ISBN 9788185990354 https://web.archive.org/web/20120501043412/http://voiceofdharma.org/books/hhce/
About John Muirs Matapariksha

Original works of Rabindranath Vol. 24 page 375, Vishwa Bharti; 1982.

The Way to Divine Knowledge (1762).
Context: If Reason seems to have any Power against Religion, it is only where Religion is become a dead Form, has lost its true State, and is dwindled into Opinion; and when this is the Case, that Religion stands only as a well-grounded Opinion, then indeed it is always liable to be shaken; either by having its own Credibility lessened, or that of a contrary Opinion increased. But when Religion is that which it should be, not a Notion or Opinion, but a real Life growing up in God, then Reason has just as much power to stop its Course, as the barking Dog to stop the Course of the Moon. For true and genuine Religion is Nature, is Life, and the Working of Life; and therefore, wherever it is, Reason has no more Power over it, than over the Roots that grow secretly in the Earth, or the Life that is working in the highest Heavens. If therefore you are afraid of Reason hurting your Religion, it is a Sign, that your Religion is not yet as it should be, is not a self-evident Growth of Nature and Life within you, but has much of mere Opinion in it.

Online promotional material (6 June 2006).
2006

Source: Autobiography (1873), Ch. 2: Moral Influences in Early Youth. My Father's Character and Opinions.

https://archive.org/details/autobiography01mill/page/45/mode/1up p. 45

2009, A New Beginning (June 2009)
Context: People in every country should be free to choose and live their faith based upon the persuasion of the mind, and the heart, and the soul. This tolerance is essential for religion to thrive, but it is being challenged in many different ways. […] Freedom of religion is central to the ability of peoples to live together.

Speech in Merthyr Tydfil (November 1890), quoted in Thomas Jones, Lloyd George (London: Oxford University Press, 1951), p. 11.
Backbench MP

Young India, (Bulletin), 2-10-1930, p. 2 In: My God (1962), Chapter 13. Pathways of God http://www.mkgandhi.org/god/mygod/pathwaystogod.html, Printed and Published by: Jitendra T. Desai, Navajivan Mudranalaya, Ahemadabad-380014 India
Posthumous publications (1950s and later)
Context: All faiths are a gift of God, but partake of human imperfection, as they pass through the medium of humanity. God-given religion is beyond all speech. Imperfect men put it into such language as they can command, and their words are interpreted by other men equally imperfect. Whose interpretation must be held to be the right one? Every one is right from his own standpoint, but it is not impossible that every one is wrong. Hence the necessity for tolerance, which does not mean indifference towards one’s own faith, but a more intelligent and purer love for it. Tolerance gives us spiritual insight, which is as far from fanaticism as the north pole is from the south. True knowledge of religion breaks down the barriers between faith and faith and gives rise to tolerance. Cultivation of tolerance for other faiths will impart to us a truer understanding of our own.