Answer
Dōgen's eminent teacher was Tiantong Rujing, a renowned Zen master of the Song dynasty. Rujing's teachings profoundly influenced Dōgen's understanding of Zen and shaped his approach to meditation and spiritual practice. Under Rujing's guidance, Dōgen gained deep insights into the essence of Zen, which he later disseminated in Japan, becoming a pivotal figure in the transmission of Zen Buddhism.