Bhagavad Gita Verse 12, Chapter 15

yadaadityagatam tejo jagadbhaasayatekhilam |
yachhandramasi yacchaagnau tattejo viddhi maamakam || 12 ||
 
That splendour which resides in the sun and illumines the entire world, that which is in the moon and in fire, know that splendour to be mine.
 
yat : that
aadityagatam : resides in sun
tejaha : splendour
jagat : world
bhaasayate : illumines
akhilam : entire
yat : that
chandramasi : in the moon
yat : that
cha : and
agnau : in fire
tat : that
tejaha : splendour
viddhi : know
maamakam : mine
 
So far we learned about the nature of the individual soul, the jeeva. But if that is all we focus on, we will have incomplete knowledge about our true nature. When we look around us, we see the world in all its beautiful yet complex glory. We need to investigate into the true nature of the world, and realize our identity and connection with that as well. With this view in mind, Shri Krishna now begins to explain his connection with the world around us.
 
He starts this topic by asserting that the splendour of the sun, the moon, and of fire is possible only because of Ishvara's splendour. We have tremendous awe for the sun's energy, without which life on this earth will not be possible. Shri Krishna says that the sun’s splendour is not its own. It comes from the splendour of Ishvara. Symbolically, the sun represents the organs of perception such as the eyes, ears, nose and so on. Therefore, whenever any sentient being in this world, from a single celled amoeba to a human being becomes aware of something, that awareness, that consciousness, is the power of Ishvara at work.
 
So whenever we see awareness manifest itself in any organism, we should remind ourselves that the one Ishvara giving awareness to us is the same Ishvara giving awareness to the organisms in the world. In this manner, we can realize the identity of our nature with the world through the common link of awareness.
 
Furthermore, both the moon and fire derive their energy and splendour from the sun. The moon reflects the light of the sun. Fire also is the manifestation of the sun's energy on a much smaller scale. Therefore, energy in any form, whether it is dazzling like the sun, cooling like the moon, or warm like fire, is nothing but Ishvara’s energy. How does this energy manifest itself in the world? Shri Krishna explains that in the next shloka.