Drubchen is an advanced form of ceremonial practice in Vajrayāna Buddhism. One of the main differences between exoteric or sūtra form of Buddhism and esoteric or tantric form of Buddhism is the visualisation and worship of deities or Buddhas. Vajrayāna Buddhism has a lot of meditation on the Buddhas in different forms – peaceful, wrathful, celibate, in sexual union, multi-armed and multi-headed, etc.
In a tantric deity practice, a practitioner visualises the deity, sometimes surrounded by many other deities, and mantras at the heart of the deity. It also consists of visualisation of many activities such as offering, prostration, casting forth and dissolution of rays and mantras and efficient channelling and tuning of spiritual energies. The whole world and surrounding are visualized as a pure maṇḍala or configuration of enlightened beings and energies.
There are many stages in such meditation on the deity and mantras. The first one is normally the full awareness of the state of emptiness. From the state of emptiness, one does the meditation on the luminous appearance or clarity of one’s mind. Such nature of empty luminosity is then embodied or expressed in the form of a seed syllable or letter, which the practitioner clearly visualizes. The seed syllable is then transformed into many mantras or enlightened symbols and gestures and eventually into the full form of the Buddhas. Finally, when the meditator has mastered these phases of meditation, he or she engages in a group session with other colleagues and spiritual companions in order to boost his meditation. This is called tsombu tsogdrub and is commonly known as drubchen these days.
Thus, in the advanced drupchen practice, the practitioners would have normally finished the earlier stages and then come together to do the practice in a group. They go through the stages of meditation and chanting together, often considering the main guru as the central deity. Drupchen is thus a group psycho-spiritual exercise in order to enhance the power of meditation through deity visualisation and chanting of mantras. The duration of such session can last from a week to six months. In brief, it’s a meditational communion based on the visualisation of a deity and mantras and not everyone is qualified to take part in it. What goes on today as drukchen ceremony is largely symbolic enactments of the real thing.