Tantras are techniques, skillful ways of handling the mind. It is skill in action. The tantric methods make use of yantras and mantras which together help a seeker to transcend the body consciousness and be established in the space of the Self. Tantras make use of these yantras and mantras with a specific purpose to heal or create harmony at the physical, emotional and spiritual levels. This is the real purpose.
However tantra has been understood as a negative term. This is what happens when one tries to use the techniques with a selfish or harmful intention. It requires a mature intellect and pure heart to wield these techniques in their full capacity for the benefit of humanity.
The study of tantras is like an applied science for the mind. It is a higher psychology which involves moving through the body to the higher Self. It helps till the ego level. Only mantras can transcend the ego level to the level of the Self. Because we are in the body, we need to take care of the body. Tantras can cleanse the body and mind of any vikarasor distortions. When used for general well-being, it has curative effects for psychiatric ailments, fear psychosis and so on. One can exercise power on the mind through the tantras.
Tantra is a research field. Real tantric scholars are a few. It is like holding a PhD. A doctorate is not awarded for individual benefit. There is value in it only when the study is beneficial for humanity. It is the same with tantras. In fact, if it used with a narrow-minded motive, then there are side-effects. Any seeming benefits are also short-lived. A child cannot attempt a PhD.
Similarly, if one attempts the tantras without being qualified and without the proper guidance and expertise, it can instead create illusions in the mind which in Sanskrit is refered to as Yoga maya. Further, failure in the attempts can lead to depression. Even among the mature beings, not all need to do PhD. The path of tantras has to be treaded very carefully. It is bound by cause and effect and the laws of karma. In research, learning happens to a great extent through trial and error. Even in this process, if any harm comes to anyone, the research scholar will reap the consequences.
Tantras give access to the ancestors. They enable travel in time, both forward and backward. If the tantras are available in the hands of an immature or selfish person, using it for short-term benefits, it can take a destructive nature. That is why it was guarded as a secret. In this creation, it is difficult to categorize anyone as a good or bad person. Transformation is continuous. That is why the gurus would study the disciples and only the eligible student is given this field of knowledge.
The Guru knows when our intellect is mature and heart is pure. The Guru knows when we are ready to receive this knowledge such that it can be of use to the society. Only a lit candle can light another. That is why it is important that we receive this knowledge from the Master. Otherwise, we can find many yantras and mantras and their tantras in the books and even on the internet but it may not help us in any way. Instead it could be harmful if not used correctly.
This skill involves a fine balance between intelligence and innocence. Without innocence, intelligence can cross over and become manipulative. It is like balancing on a razor’s edge. Tantras are like double-edged swords. You can remove the tumor with it but if you are not careful, you can hurt the limb. In the hands of a child, it is not of much use. Instead it can be dangerous. But in the hands of a surgeon, it is life-saving. The knife in itself has no value. Following any extreme can be harmful to oneself and to others. That is why the supervision of the guru is essential. The guru teaches you to be skillful in action. He guides you to be intelligent without losing your innocence. He shows you how to follow the middle path.