The Brihat Tantra Sara (Great Essence of Tantra) is a revered compendium attributed to the medieval Tantric scholar Krishnananda Agamavagisha. This text synthesizes teachings from various Tantric traditions, including the Shakta, Shaiva, and Vaishnava streams, and is particularly known for its detailed dhyana mantras (meditation verses) that facilitate visualization of deities. The dhyana mantras from this work are chanted to invoke the presence of specific deities, often the Dasha Mahavidyas (ten wisdom goddesses) such as Kali, Tara, and Tripura Sundari, as described in the 'Mantra Mahodadhi' and 'Shaktisangama Tantra'. Each dhyana mantra contains precise phonemic sequences (beej-aksharas) like 'Kreem', 'Hreem', and 'Shreem', which are believed to encode the subtle energies of the deity. For example, the beej 'Hreem' is associated with the goddess Bhuvaneshvari and represents the cosmic creative vibration. The traditional purpose of these mantras is to purify the mind, awaken kundalini, and grant siddhis (spiritual powers) as outlined in the 'Brihat Tantra Sara' itself. They are recommended for chanting during the early morning or midnight, with a minimum of 108 repetitions using a rudraksha mala, in a clean, solitary space. Practitioners should observe strict dietary and behavioral regulations (yama-niyama) and receive initiation (diksha) from a qualified guru, as the mantras are considered powerful and potentially destabilizing if misused. Cautions include avoiding chanting during periods of impurity (e.g., menstruation, mourning) and never using the mantras for harmful intentions. The ultimate goal is the realization of non-dual consciousness (advaita), where the practitioner merges with the deity's essence, as affirmed in the 'Devi Mahatmya' and 'Lalita Sahasranama'.
The great essence of Tantra, the comprehensive compendium of teachings.