How does karma work?

The following passage was taken from Sri Chinmoy?s book entitled Death and Reincarnation:

    We are carrying the past inside us. It is a continuous flow; ?as you sow, so you reap.? If we do something wrong, we have to know that either today or tomorrow, either in the physical world or in the inner world, we will get the result. If I constantly steal, one day I will be caught and put into jail. I may not get caught today, but one day I will be caught. And if I do something good, if I pray, if I meditate and do divine things, I will get the result of this also. Sometimes we see someone who has done something wrong enjoying the world. But perhaps he did something extraordinary, something wonderful in his immediate past incarnation, and now he is having the result of his good action, while the results of his bad deeds have not yet started to bear fruit. In the evening of his life, or in a future life, he will definitely be punished.

     In the case of an ordinary, unaspiring person, karmic dispensation is unavoidable, inevitable. The law of karma is always binding; like a snake it will coils around him. He has to pay the toll, the tax; the law of karma is merciless. But again, there is something called Divine Grace. I was ignorant and I did a few things wrong. But if I shed bitter tears and cry for forgiveness, then naturally God’s Compassion will dawn on me. When a person enters into the spiritual life, his karma can easily be nullified if it is the Will of God operating through a spiritual Master. Slowly God?s infinite Grace can nullify the results of his bad karma and expedite the results of his good karma. If a seeker not only wants the spiritual life but also sincerely practises the spiritual life every day, then he can stand above the law of karma, for God is bound to shower His boundless Grace on the devoted head and heart of the aspirant. Of course, I cannot go on doing some undivine thing and feel that God will always forgive me. No. But if God sees a soulful cry looming large from within, if He sees that I am sincere and aspiring and want to be free from the meshes of ignorance, He will not only forgive me but He will also give me the necessary strength not to make the same mistake again.

     When we come back in our next incarnation, naturally we have to start our journey according to the result of our past karma. If we have done many things wrong, we cannot expect to realise the highest Truth in our next incarnation. But if God’s Grace is there, we can easily nullify the wrong things we have already done during this life.

?Sri Chinmoy, Death and Reincarnation