At this critical juncture, Mahendranath's nephew took him to the temple garden of Dakshineswar Kali Temple, where Ramakrishna, a mystic and the chief priest of the Kali temple lived. It was here that Gupta met Ramakrishna for the first time and this meeting was a turning point in his life. Years later, when Mahendranath was asked about the greatest day in his life, he said, "the day I had my first darshan of Thakur [Ramakrishna] in February 1882." According to other traditional accounts, Mahendranath related that he may have met Ramakrishna for the first time when he was four years old and became separated from his mother while visiting the Dakshineswar Kali Temple. He began crying, and a blissful and youthful man came up and consoled him. He believed it to be Ramakrishna, who was then a priest at the Kali temple. M had the habit of maintaining a personal diary since the age of thirteen. M met Sri Ramakrishna in 1882 and attracted by the latter's teachings, started to maintain a stenographic record of Sri Ramakrishna's conversations and actions in his diary, which finally took the form of a book "Sri Sri Ramakrishna Kathamrita". Initially when M began writing the diaries, he had no plans of publication. Regarding his methodology M wrote,  In each of his "Kathamrita" entries, M records the date, time and place of the conversation. The title "Kathamrita", literally "nectarine words" was inspired by verse 10.31.9 from the Vaishnava text, the "Bhagavata Purana". Both Sri Ramakrishna's wife, Holy Mother Sarada Devi, and Swami Vivekananda later testified to Mahendranath's faithfulness to Sri Ramakrishna's words. The first four volumes were published in 1902, 1904, 1908 and 1910 respectively and the fifth volume in 1932, delayed because of M's health problems. The "Kathamrita" contains the conversations of Sri Ramakrishna from 19/26 February 1882 to 24 April 1886, during M's visits. The "Kathamrita" is regarded as a Bengali classic and revered among the followers as a sacred scripture. Famous translations of "Kathamrita" include works by Swami Nikhilananda(1942), and Dharma Pal Gupta.