"Religion means...spiritual realization."

Do not care for doctrines, do not care for dogmas or sects or churches or temples. They count for little compared with the essence of existence in each man, which is spirituality, and the more this is developed in a man, the more powerful is he for good. Earn that first, acquire that, and criticize no one; for all doctrines and creeds have some good in them. Show by your lives that religion does not mean words or names or sects, but that it means spiritual realization. Only those can understand who have felt. Only those who have attained to spirituality can communicate it to others, can be great teachers of mankind. They alone are the powers of light.

That’s Swami Vivekananda telling us the message of his guru, the famous Ramakrishna Paramahamsa (1836-1886). Ramakrishna Paramahamsa's search for God, the life of renunciation and austerity he led, are indeed remarkable. The Wikipedia link I've provided gives all the details, but the story is most poignant in the words of his disciple -- it is from one of Vivekananda's essays, Great Teachers of the World that I've excerpted the above.