What we posses, posseses us.

The fifth and final yama or "great vow" as taught by Patanjali in the Yoga Sutras is aparigraha. 
 
Broken down into it's sanskrit parts, 
pari means "that which is all around us"
graha means "to grab or to grip"
a is a prefix that negates a word

Put it all back together and Patanjali says, "Don't grab onto everything that is around you (or in a simplified version), don't be greedy!". He goes further by saying that when we are established in non greed, we will come to know the meaning of our lives.

The ancient Indian practice of trapping monkeys is often used to describe this yama.

Long ago in order to catch monkeys, hunters would carve out a coconut leaving a hole just big enough for a monkey's stretched out hand to fit through. Then they would anchor the coconut to the ground. Rice or sweet treats would be placed inside of the coconut as bait. The hungry monkeys would smell the rice and squeeze their hands through the hole and greedily grasp the goodies in their fists. When they tried to pull their hand back out, their tightly closed fist was too big to fit. As they struggled to pull their bounty out of the coconut, the hunters could easily capture them. What the monkeys didn't realize was that it was their own unwillingness to release the grip on their prize that caused their self imposed prison.

They say that "what we possess, possesses us".

Like the monkeys in the self imposed coconut trap, all of the stuff that we greedily aquire begins to weigh us down, and our best attempts to be free while holding onto it just leaves us feeling trapped. 

We aquire and hold onto material possessions, old beliefs and thoughts, grievences of the heart, and identifications with our physical bodies long past their usefullness. 

Its okay and often times necessary to aquire new things. Keep in mind however, that when we aquire new things, new thoughts, new ideas, and new feelings, we must also release or let go of the old ones so that we will have the space to take in what's new.

Giving away money and material possessions to those in need, letting go of grievences through forgiveness, and 
leaving the past in the past, will leave us feeling lighter and may even bring us closer to knowing the true meaning of our lives.

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