"The Principle of Causality (Karma)
Every cause has an effect and every effect has a cause. Everything happens according to the law. Luck is only a name that is given to an unknown law. There are many planes of causality, but nothing escapes the law." The effect may come later in our next re-incarnation[s].
Is one of the seven principles of the Kybalion.
In physics when we apply a force to a wall, the wall hits back with the same force but in the opposite direction, towards us. For every action there is the same reaction in nature and when we love, hate, help, kill, etc. we are inheriting a reaction of the same force towards us. It may not come right away, but it will come on this life or on future ones.
When we kill people regardless of the reason, if it was ordered to us, if it was an accident or if it was on purpose, we will be killed most likely on future lives. "You shall not kill" as one of the 10 commandments.
When we kill animals, besides the damage done to our bodies, we get karma of killing beings and that creates negative karma to us, our city, our state, our country and it may come as future wars, calamities, etc. where we get killed back.
The poor animals generate fear knowing they're going to be killed and those negative vibrations also stay in our environment as well as in the astral world. Those vibrations with time, could also bring mental problems to our generations exposed to them.
All beings, us and animals included generate vibrations (can be measured by science) that together as a whole attracts similar, either negative or positive outcomes. This includes wars, hunger, abundance, homelessness, etc. It also includes the prediction of old civilizations and our history of attracting celestial disasters like asteroids hitting earth.
Each one of us with every act is determining our future, by killing any animals we are bringing killing to us in the future.
It's time to elevate our consciousness, where nowadays we can replace all animals and animal byproducts by other products without killing animals. It's better for our health, the environment and our karma.
Peace
Link
https://en.m.wikipedia.org/wiki/The_Kybalion