Yantra drawing is sometimes offered as part of yoga courses or meditation workshops. This practice is a good example of how Far Eastern religious practices are introduced into Western culture, often without the participant being aware of this religious background.
Yantras are ritual diagrams that come from Hinduism or Tantrism (an esoteric form of Hinduism). They are used for meditation or as part of an initiation (= introduction of outsiders). The term „yantra“ comes from Sanskrit यन्त्र , from yam „to support“, „(to) hold“.
The online encyclopedia Wikipedia describes the function of yantras as follows: „A yantra is considered a representation of the „divine“ and can be seen as a physical expression of a mantra: The mantra represents an „aspect of the divine“ in the form of a sound, while the yantra represents it in the form of a geometric figure.
Yantras play a particularly important role in the religious life of followers of Shakti, the female form of the ‚divine‘. They may be drawn on the ground, on paper or carved into metal plates. These symbols represent the formless aspect of the „Goddess“. In worship, a puja ceremony, they may take the place of a statue or image. By chanting mantras, devotees believe that the Goddess herself manifests in them and is present through them. In a Devi puja (Devi = goddess), a yantra is often central. It is said to serve to „open the heart“ and „unite with the divine power“. The Shri Yantra is said to bring „victory over evil“.
A yoga seminar brochure praises yantras: “ …as sacred geometric diagrams. They are used to awaken the energy of certain deities or planets and to get in touch with our inner being […] In this workshop […] we will learn how to use this powerful image as a means of transformation, inner protection and healing in our lives…“.
In the Sanskrit text „Lalita Sahasranama“, which is used to worship the „divine mother“, it says: „I bow to the Goddess who is ‚the Soul of All Yantras“.
Judgement from a Biblical Perspective: Yantras and mantras invoke the Hindu deities behind them, as explained and documented above. From a Christian, biblical point of view, this is idolatry in its highest form. The ritual exercises are often performed in a room with some kind of altar, often together with idol statues and the image of a guru. (Source: netzwerk-esoterik-ausstieg.de)