Whatever insight we may have, as soon as we would wish to communicate and express that insight we need language. So besides training in meditation which facilitates insight, training in language is extremely important. Over the centuries the old masters have developed a highly effective language that sets forth the guiding principles and clarifies the various stages of practice through beautiful images and analogies. We can find this language in the Indian Sutras and the works of Chinese, Tibetan, Japanese, Korean and other masters. They all speak with distinct voices and yet they share remarkable similarity.
The same seems to be true for body language. Throughout the history of Buddhism many forms of ritual have been created, and some of these have been preserved to this day. Why? They have proven to be effective practices for people in very different cultures. The form and lay-out of the temple, the sitting posture, bowing and making offerings, the chanting of texts and the various choreographies that enable a group to harmonize and express one intention together are all forms of body language that can communicate beautifully the core of Buddhist teaching. Just to see somebody sitting in deep samadhi or making a sincere bow can often be more inspiring than any spoken word.
Of course language does change, and it needs to in order to stay alive. But language can only change slowly, otherwise we may not understand each other anymore. Trying to express our understanding without training in the verbal and ritual language of the old masters would be like inventing our own Esperanto, which may not survive one generation. So in addition to meditation, study and ritual are essential elements of training.