In the Vedic context, a guilt (enas) is incurred by an immoral action, something that is primarily against someone, but also against yourself or the natural divine concepts of Devas. Whatever is done against the Ṛta, against the ordinances of conscience (Adityan vratas) incurs enas.
Guilt is basically a force that should come from your conscience to let you know of the right path to tread. It is the responsibility of the society, of the parents and the individual to equally inculcate the feeling of guilt towards what is not in accordance with empathy or Ṛta. If a person commits something that is supposed to be wrong as it makes someone suffer, but doesn’t feel guilty about it, that is a dangerous failure of the society, in failing to instill righteousness.
Like children who when parented with rewards against doing evil resulting in them being materialistic and looking for an opportunity to go for a shortcut, a people who are instructed with a rewarding individual ideology like a great rebirth or heaven tend to be materialistic the same way, ultimately. Punishment and reward is good when there is someone who has done something that is radically empathetic or radically out of phase compared with social norms. Else, every “good karma” being “rewarded” and “bad karma” being “punished” through an individualistic, automated nature/God is an ideology that will not raise people to the Aryan righteousness and nobility of thoughts, to the Ādityan conscience and consciousness that is built on harmony, Ṛta.
So what will happen if someone does a wrong thing to another but feels no remorse? The society should see that such a person is punished so that justice is ensured, and a principle is set, a limit is set. This is why kings are supposed to be the implementers of Ṛta in our world. If someone wrongs society and doesn’t get the punishment, then the guilt befalls the king/the people who are responsible for the justice in the society. This will trigger the instincts of people to see that society accepts it as right and an incentive to showcase their instinctive actions that might be disastrous. You might think of it like, such a person’s bad traits are “reborn” in the society each time multiplying until the society as a whole strives to end it.
Now, coming to what guilt can create. Guilt creates a tight spot for us instead of the Ādityan Ṛta that is based on the unlimited mind and purity of our spiritual existence. This guilt eventually burns us from within. It affects the “us” in us, we tend to lose hope on ourselves, we tend to hate ourselves and this can turn our life into disaster. If you feel genuinely guilty about something for which you feel nature or society has not provided justice (in the case of doing something against yourself or Ṛta) and you are sure that you will never do it again – that means your conscience has developed and held you responsible for the Ṛta only now. You then surrender to the discriminating, wise power of conscience, the great Rājā Varuṇa and pray to him to release you from his guilt.
The notion of justice, good and bad all exist meaningfully only in a self-conscious social perception. If your conscience is not evolved (but had the power to evolve) to discriminate between good and evil, can you alone be held accountable for your actions, which are merely natural and instinctive actions of you? (Your instincts are shaped mostly by society and people in sphere of your influence) These are complex questions in ethics. The satisfactory, real solution we might give is to implement the notion of Ṛta and held the steadfastness to Ṛta as a marker of your right to exist. A lion killing deer is the Ṛta, however a man killing another man for food would not be – because our morals are evolving differently. Morals in the stone age should differ from morals in the iron age. Morals of the 21st century should differ from morals which we might reach in the next century by the virtue of our changing culture. Culture and self-acceptance greatly influences the factor of “guilt” and “suffering” in people. For instance, death is an accepted form of suffering. So there is nothing unnatural about it. A deer is bound to naturally suffer death most likely from a predator who has no choice otherwise. That is natural, there is no “suffering”. A woman takes pain to give birth to a baby. It is not considered “suffering”. You might toil hard to earn your food, that is not considered suffering. “Suffering” comes as an ethical problem where there is choice on the side of the one who inflicts from not doing so. This is controversial, but just introspect the ethics of twenty first century people killing animals for sport or eating meat. It will go on unless the conscience of the society as a whole develops. And till then, the notions which justify this behaviour will also be present in the society. (speciesism, exploitation of the weaker, jungle laws) This is the way of nature. It is for us to evolve, else we face the consequences as a whole.
The objective morality system is basically against the progressing flow of Ṛta. We cannot decide any objective good or evil other than perhaps acting against our empathetic conscience which shows the ṛta. So, everyone should be accountable only so much as to act in accordance with Ṛta, which everyone should strive to establish as an individual, as a community, as a nation, as a living world that strives for progress and existence, thus following Ādityas.