In this post, we will dive deep into the subject of classical hatha yoga postures. Read this post in combination with our other guide on seven mistakes people make when it comes to these hatha yoga postures. I hope this helps prevent you from making the same mistake.
Not all body postures are yoga postures.
We can move our bodies into different postures. But, did you know that not all body postures are yoga postures? Why not you may ask?
The yogic science has a long and ancient history. Enlightened beings from all over history have meticulously observed their bodies and reached a certain state of “knowing”. These beings have obtained a profound understanding of the human mechanism and its relations to the cosmic universe.
Out of this thorough understanding, the enlightened masters came to know that certain postures can align our individual energy body with celestial geometry. Ultimately, this alignment can lead to the experience of being one with the universe. Thus, yoga! Which means union. Let me show you an example here.
This image shows two Isha Hatha Yoga teachers doing a tree posture. Their heels are blocking the root energy point and their thumbs are pressing against the centre energy point. This enables the upraise of energy in the system, activate the centre energy point and bring a certain inner balance. It will not work in the same way if you just somehow copy the tree posture, without knowing the energy physiology of the human body. How you place the hand and feet in classical hatha yoga is extremely important.
Hatha yoga is not an exercise form but a “powerful process to enhance our perception”.  These postures are also known as Yogasanas – literally meaning the postures that unite the individual with the universe.
Why are there only 84 fundamental hatha yoga postures?
Even though more than 600 hatha yoga postures are practiced around the world. Sadhguru says that only 84 fundamental hatha yoga postures or yogasanas are available.  So, why only 84?
You might have heard of the Big Bang theory. According to yogic science, 84 Big Bangs took place in the making of the universe. This process created 84 universes. The memory of these 84 creations is recorded in the human body in a codified way.  Sadhguru explains that 84 of the energy centers in our body reflect the making of the universe. This is why the human body is seen as a manifestation of the great cosmos.
Let’s use a tree as an analogy. If you observe the annual growth rings of a tree, you can trace back the exact year the tree was formed. You can also tell the climate and atmospheric conditions.  Although not quite as visible as the annual growth rings, the creation has also left its imprint on our bodies.
These 84 fundamental hatha yoga postures represent 84 alignments. When the alignment happens, we can release and activate the codified memory within us. Therefore, hatha yoga postures are not simple body postures. These are 84 powerful doorways for us to attain the ultimate union and gain knowledge of existence. 
Why are classical hatha yoga postures so important?
Many teachers have evolved different modifications and variations. This is why there are more than 600 hatha yoga postures practiced worldwide. However, only those 84 fundamental postures are the true representations of the creation’s imprint. Therefore, some modifications of the postures bear the risk of deviating us from its original form. Let me show you another example of a typical posture.
This posture is referred to as hand to foot. In Classical Hatha Yoga, it is emphasized that the heels are touching in this posture. When the heels are touching, the Muladhara is locked and this helps the upraise of energy in this position. Many people are modifying this posture with feet apart. Then, it will not have the same effect.
This is one of the important reasons why Sadhguru trains us to revive classical hatha yoga, to transmit the original form of the hatha yoga postures. Through these classical hatha yoga postures, we can directly get in touch with the original purpose and experience its immense power and benefits.
Why are not all 84 postures taught in the Isha hatha yoga series?
Sadhguru has carefully selected 21 hatha yoga postures for the beginner sequence of Yogasanas practice. A few advanced ones have been added afterwards.
Why has Sadhguru chosen not to teach all 84 postures? This is a frequently asked question. He explains that all 84 will be too much to learn. Furthermore, the first quarter of the asanas is preparatory in nature.  By practicing these yoga postures, the body slowly becomes completely at ease on its own. 
The remaining asanas are transformational in nature. They boost the energy in a certain way. Therefore, it is crucial to establish a balanced foundation before anyone takes this to a higher level.
You will be relieved to know that learning all the 84 postures is unnecessary to reach the ultimate union. “If one masters a single posture and approaches the remaining 83 through that, one can know everything that has happened in creation until now.” – Sadhguru . This is known as Asana Siddhi:
In the next part, I want to point out 7 typical mistakes people make when they try hatha yoga postures. Hopefully, this can help you to avoid them. Click here to read: Hatha Yoga Postures: 7 Typical Mistakes People Make
 Isha article, Hatha Yoga Guide: Science, Benefits and Insights, 9th April, 2015, https://isha.sadhguru.org/global/en/wisdom/article/hatha-yoga-benefits, retrieved on 4th April 2021
 Isha article, Yogasanas – Creating Healthy, Joy and Blissfulness, 13th April 2015, https://isha.sadhguru.org/global/en/wisdom/article/yogasanas-creating-health-joy-blissfulness/, retrieved 4th April 2021
 Excerpts from Sadhguru’s talks, Yogasana: Introduction, D15-10181942, Hatha Yoga Teacher Training material.
 Excerpts from Sadhguru’s talks, The human system, Physical and Non-Physical Dimensions, Hatha Yoga Teacher Training, p12, p13, p146-153
 Wikipedia, Dendrochronology, https://en.wikipedia.org/wiki/Dendrochronology retrieved 28 April 2021
 Isha article, Asana Guide – align with the divine, https://isha.sadhguru.org/yoga/yoga-articles-hatha-yoga-asanas/asanas-guide/, retrieved 4th April 2021
 Isha article, Why a set of 21 Yogasanas? https://isha.sadhguru.org/yoga/yoga-articles-hatha-yoga-asanas/set-twenty-one-yogasanas/, retrieved 4th April 2021