The understanding of Buddhadharma is acquired from threefold study: the first is learning from hearing or from reading. Without hearing from a teacher or reading from books we do not have the information, so that is the first stage. The second stage is analysing them by yourself, through an analytical and rational mind. The third stage is that you meditate upon it and have the direct perception. So these three stages are in sequence and depend on each other. Therefore reading and attending teachings is absolutely necessary for the understanding of Buddhadharma.

-- 5th Samdhong Rinpoche, Lobsang Tenzin