B.G 15.01

The auspicious Lord said:

They speak of the imperishable peepul tree having its roots above and branches below. Its leaves are the Vedas, i.e. knowledge; he who knows it is the knower of the Vedas.

Gīta Tātparya 15.01

Here, the union of consciousness and matter is declared to be a tree. The earth, the deity, is like clay, the insentient. Lord Hari, due to the superiority of the roots, is remembered as having roots above. From there, the inferior - 'mahat aham', i.e. the great ego principle, intellect - joined with elements, emerged. The branches are the Vedic hymns, and the leaves represent desires and liberation.

It elaborates on the topics touched on in the thirteenth chapter (13.06).

"Lord Hari is the distinct root of the world tree. The earth, possessing qualities such as sattva, represents both the conscious and unconscious aspects of nature, being the divine root. Here, the union of consciousness and matter is declared to be a tree. The earth, the deity, is like clay, the insentient. Lord Hari, due to the superiority of the roots, is remembered as having roots above. From there, the inferior - 'mahat aham', i.e. the great ego principle, intellect - joined with elements, emerged. The branches are the Vedic hymns, and the leaves represent desires and liberation."