Indian Mahasiddhas, has a series of asanas and pranayamas (such as tummo) which resemble hatha yoga. Laya and kundalini yoga Laya and kundalini yoga, closely associated with hatha yoga, are often presented as independent approaches. According to Georg Feuerstein, laya yoga (yoga of dissolution or merging) "makes meditative absorption (laya) its focus. The laya-yogin seeks to transcend all memory traces and sensory experiences by dissolving the microcosm, the mind, in the transcendental Self-Consciousness." Laya yoga has a number of techniques which include listening to the "inner sound" (nada), mudras such as Khechari and Shambhavi mudra, and awakening kundalini (body energy). Kundalini yoga aims to awaken bodily and cosmic energy with breath and body techniques, uniting them with universal consciousness. A common teaching method awakens kundalini in the lowest chakra and guides it through the central channel to unite with the absolute consciousness in the highest chakra, at the top of the head. Reception by other religions Christianity Some Christians integrate physical aspects of yoga, stripped from the spiritual roots of Hinduism, and other aspects of Eastern spirituality with prayer, meditation and Jesus-centric affirmations. The practice also includes renaming poses in English (rather than using the original Sanskrit terms), and abandoning involved Hindu mantras as well as the philosophy of Yoga; Yoga is associated and reframed into Christianity. This has drawn charges of cultural appropriation from various Hindu groups; scholars remain skeptical. Previously, the Roman Catholic Church, and some other Christian organizations have expressed concerns and disapproval with respect to some eastern and New Age practices that include yoga and meditation. In 1989 and 2003, the Vatican issued two documents: Aspects of Christian meditation and "A Christian reflection on the New Age," that were mostly critical of eastern and New Age practices. The 2003 document was published as a 90-page handbook detailing the Vatican's position. The Vatican warned that concentration on the physical aspects of meditation "can degenerate into a cult of the body" and that equating bodily states with mysticism "could also lead to psychic disturbance and, at times, to moral deviations." Such has been compared to the early days of Christianity, when the church opposed the gnostics' belief that salvation came not through faith but through mystical inner knowledge. The letter also says, "one can see if and how [prayer] might be enriched by meditation methods developed in other religions and cultures" but maintains the idea that "there must