1. Bhagavad-Gita As It Is. Chapter 15.
Text 1.
The tree of
Material Existence

2. Text 1 çré-bhagavän uväca ürdhva-mülam adhaù-çäkham
açvatthaà prähur avyayam
chandäàsi yasya parëäni
yas taà veda sa veda-vit
The Supreme Personality of Godhead said: It is said that there is an imperishable banyan tree that has its roots upward and its branches down and whose leaves are the Vedic hymns. One who knows this tree is the knower of the Vedas.

3. Banyan tree of entanglement
One may question, "What about the Vedas?"
The entanglement of this material world is compared here to a banyan tree.
One who is attached to this tree, there is no possibility of liberation.
If one can understand this indestructible tree of illusion, then one can get out of it.

4. Cutting off the tree
The basic principle of devotional service is detachment from material activities and attachment to the transcendental service of the Lord.
This reflection of the spiritual world is situated on desire, just as a tree's reflection is situated on water.
One who wants to get out of this material existence must know this tree thoroughly through analytical study. Then he can cut off his relationship with it.

5. Origin of banyan tree.
The material world is the perverted reflection, so the spiritual world must have the same variegated ness, but in reality.
A reflection is temporary, for it is sometimes seen and sometimes not seen. But the origin from whence the reflection is reflected is eternal.
The purpose of the Vedas, as disclosed by the Personality of Godhead Himself, is to cut down this reflected tree and attain the real tree of the spiritual world.