Karma or action is the pivot around which life revolves. Action comes from desire emerging from thought. And thought comes from vasana, the inborn urge, deep-rooted inclination. When you have a vasana for music, thought for music arises in your intellect. This consolidates as desire, and manifests as action. Action further creates an imprint, vasana, for music. Thus you are a victim of your vasanas in the present. This is referred to as fate or destiny.
All other species have to act in line with their vasanas. Only human beings are gifted with choice of action. With purushartha or choice, you determine your future. Prarabdha, destiny, is the sum total of all your past purusharthas. It is irrevocable. So if you look at your past you are a victim. With reference to the future, you are a victor. At each juncture you are free to choose the way you think, desire or act. Once chosen you are a victim of its effect.
Think a negative, hateful thought. That moment, you become a little more evil. The effect is failure, misery and sorrow. You carelessly entertain negative thoughts. When the collective effect of all this negativity hits, you wonder why tragedy has struck!
Think a positive, loving, elevating thought. That instant, you become a little more divine. The effect is good fortune, happiness and spiritual growth. You meet with serendipitous experiences.
Free will is the key to your emancipation. Irrespective of your past, you can choose to be better and nobler. God is only the facilitator and enabler of your actions. God has set the Law of Karma in place. It is up to you to use it for your evolution.
At death, all our desires and aspirations seem to vanish into thin air. While at birth, distinct traits and ambitions appear from nowhere. So there are causes with no known effects at death and effects with unknown causes at birth. Ancient seers in India deduced that the inner personality of a person just moves from one physical body to another. The movement of mind, intellect and vasanas from one body to another is called death of the former body and birth of the latter.
Just as a person discards old clothes to don new ones, a person discards a body and environment that is no longer conducive for fulfillment of his desires and moves to another body and atmosphere that fits the bill. Death allows you to start afresh.
The sum total of all your vasanas is called sanchita vasanas. Of these a few powerful desires that exert pressure for fulfilment are called prarabdha vasanas. They determine your birth in an environment that is tailor-made for their exhaustion. Once they are fulfilled, the next batch of desires starts playing up. So you move to another body and surrounding, customised for those prarabdha vasanas. This cycle goes on, as long as one has desires.
During your lifetime your prarabdha vasanas will be fulfilled, irrespective of what you do. You also have the option of changing your sanchita vasanas. You can add to them, subtract from them, upgrade or downgrade them or even eliminate them.
You are born in the world only to reach enlightenment. You are designed to take off into sublime spiritual realms that confer power, independence and infinite bliss. Wake up to your potential. Strive for it. Stop not, till the goal is reached.