Cause and Effect

In physics, for every action there is an equivalent reaction.
In spiritual matters there is a similar rule - the Law of Cause and Effect.
 The common phrase for this is "what goes around comes around".
People seem to have a more immediate understanding of this law because they can apply it to the negative. Ask someone about "what goes around comes around" and you will most likely get a story about how they hurt a person in some way or did something that was really rotten and it "came back to haunt"  them or an event occurred that "made it all even". 

Remember that there are no exceptions. Natural law is unbreakable.
You may have done something that was very rotten and think you have gotten away with it. There is absolutely, positively no "getting away with it".

It may take a while for the effect to come back to you. It may take years.
It may take a lifetime. It may not happen until you have left the earth plane and are living in the spirit world. But come back it will.

You may not recognize the connection between the effect and its
original cause but there is a link in there somewhere, whether you
ultimately learn what it is or not. This includes your thoughts.
Keep this in mind when you are about to unduly criticize someone
or wish something horrible upon them.

If you have done some of those "really rotten" things and are suffering from the consequences of those actions you are not doomed. Yes, you will have to pay for those transgressions and you won't get out of it. But the Law of Cause and Effect, like other Natural Laws, works in both the positive and negative directions. You can stop the negative thoughts and actions and replace them with positive ones, and before long those positive effects will be coming your way. Start with something simple like a heartfelt "have a good day" to the next person you meet. You don't have to "perform a miracle" in order for this to start working. Remember that Natural Law is always
 working. Start small and go from there. You will be amazed at the results. You will have a whole new appreciation for "what goes around comes around".

The Law Of Vibration

The Law of Cause and Effect

The law of Attraction