Bhagavad Gita Verse 5, Chapter 14

sattvam rajastama iti gunaahaa prakritisambhavaahaa |
nibandhanti mahaabaaho dehe dehinamavyayam || 5 ||
 
Sattva, rajas, tamas, these gunaas born of Prakriti, O mighty-armed warrior, bind the imperishable body dweller to the body.
 
sattvam : sattva
rajaha : rajas
tamaha : tamas
iti : these
gunaahaa : gunaas
prakritisambhavaahaa : born of Prakriti
nibandhanti : bind
mahaabaaho : O mighty-armed warrior
dehe : to the body
dehinam : body dweller
avyayam : imperishable
 
Shri Krishna beings the detailed analysis of Prakriti with two points. First, he breaks down Prakriti into its three components: the gunaas which are sattva, rajas and tamas. We have to note that the phrase “born of” in the shloka does not mean that Prakriti creates the three gunaas. It means that Prakriti itself is nothing but the three gunaas. Next, Shri Krishna states the effect of Prakriti on the Purusha, also known as the jeeva, the individual soul. He says that Prakriti binds or ties down the imperishable body dweller, the "dehi", the jeeva, to the body.
 
Let us begin by understanding what the term “gunaa” means. From our point of view, gunaa is a state of mind. In just one day, we experience calmness, passion and lethargy, which are roughly equal to sattva, rajas and tamas respectively. From a broader point of view, gunaas refer to building blocks of the universe. Inert matter is tamas, action or dynamism is rajas, and harmony is sattva. Since we are primarily interested in liberation from our sorrow, we shall focus on the impact of the gunaas on our mind rather than their impact on the universe.
 
Now, if we have repeatedly heard that our self is imperishable and can never be bound, then how can the perishable gunaas bind the self? The answer is : the gunaas by themselves do not bind us. Ignorance of our true nature, followed by our mis-identification with the body, puts us in a situation where we ourselves allow the gunaas to take over control of our life.
 
Imagine that you have parked your car on the left side of road. A car that looks just like your car is also parked on the same road, but on the right side of the road. After you come out of the building and absent-mindedly think that the other car is yours, you are trapped. You see a new scratch on the car and get upset, you get a parking ticket and have to pay the fine, and so on. The other car has not “bound” you, but your incorrect knowledge has done so. We can also go back to the example of the child watching the boxing match. He is as though glued to the screen, while his grandmother is not. The TV does not bind him since it is is nothing but millions of red, blue and green dots of light. It is the child's strong identification with the boxer that binds him.
 
Similarly, the individual soul which has mis-identified itself with the body, gets entrapped in the play of the three gunaas. In the next three shlokas, Shri Krishna takes up each gunaa one by one, and explains its power to bind the body in detail.