The Conccept of "Karma"
There has always been the articulation, of the measure that one should always ensure while executing any deed, termed as “karma” in the Hindu school of thought. The way of carrying oneself while performing any action, is said to be in harmony with, the way the emotions of the mankind are, which are to be kind and considerate towards the other beings, which can be living or non living entities.
This teaching, in numerous variants, has been professed in all the religions, which are based on some saintly character or is based in direct reference to the almighty itself, but in all these different religions, different school of thoughts, the way to conduct oneself is carried in a similar manner, which is to show courtesy towards others and be kind and considerate towards not so wealthy ones, as that, is the reason, the sharing (offering) some small percentage of ones earning is supposed to be given in donation, either to the poor or to the deity, depending upon which school of thought you correlate with.
The very essence of propagating such thoughts, is to make all the humans sympathetic towards each other and have respect towards the Mother Nature, which is offering all the things for free (no exchange of currency is undertaken when there is something to be taken from Mother Nature, so the genesis “free” is employed), that's why the very ethos of all the religions, for promulgating offerings, either to the deity or fellow living beings, is based on the genesis of love towards each other and the Mother Nature/earth.
This very idea, is based so that, the humans as being on the top of the pile of living on the earth and the most evolved beings, shall work towards preserving the earth and its fellow beings on the planet, which led to the concept of karma or deeds. To make the teachings more preserving and stringent, the fear of something bad happening was tailored into it, as the basic nature of any living being, is to preserve itself to the fullest.
Why these principles of karmas are only kind of associated with humans only, whereas there are other beings also who have the similar principles on which their life also dwells, like born, eating, reproducing and then dying, as the very basis, of all these is synonyms to us, that is being on the existence of breath in the body, or the ability of breathing. Then why, when a lion eats a small deer in front of its mother, is not said to be sinner, but when a person takes up someone in the professional or personal level and ensures others elimination, is assumed to fall in the category of sin, as in both the cases there is one who is suppressing or subdued the other in order to make itself survive, as in regard in both these instances, the emotions are said to be hurt and the act of the lion and the person are said to be insensitive towards the one they are killing/ or settling.
There are so many similar instances, which are happening, but why is that the humans are said to be cautious about their deeds/karmas whereas the other living associates on the planet, are supposed to be free from these ethics. The quest to conquer all, and to do the things which are beyond the realms of the need for survival, is one of the driving force, for the humans to be enacting their actions, whereas all the other creatures, perform all the deeds (how so ever heroic or disturbing they may be) are done just for the reason of survival.
So the hidden/unsaid feel of being the lone survivor feeling/emotion and in order to curtail this, the commandments of sharing/donating earnings/food has been promulgated by the founding fathers of society, as the feel of superior and eliminating any or all competition being dominantly present in the humans, as it is present in traces in other beings.
Does the karmas/deeds really affect the humans?, is a question which has also been reverberating in most of us, is there really something somewhere, who is taking note of the things which one is doing. Who above, or what after the present understanding on life, is a thing which has always been contestable, but if we go by the present discoveries of the science, even then, if a deed by virtue of which one tends to provide some kind of solace or comfort to other, then the chemicals within the body combine in such a manner, which gives strength and comfort to itself and same in the other order is true when someone hurts/hampers someone, by a conscious action.