Punya and papa are called adrishta – the unseen results of an action. Punya can give me joyful and papa painful experiences in life or hereafter. What we call as papa is what English literature speaks of as sin. There is no word translating punya in English. There is a universal ethical order, we’ll call it dharma, although dharma is much more than ethical order. This is true across cultures and civilizations. For example; honesty is accepted a norm and a lie is accepted as wrong everywhere whether in India, United States or in any tribe. One might not be able to always follow it but we instinctively recognize it. When one understands and is in harmony with the universal order, one lives a life of integrity.
Sin or papa would be when I go against or break this ethical order and hurt someone or cause damage without a reason. Punya would include all acts of worship to Ishwara, reaching out to help fellow human beings, all acts of service and sharing what I have. If you are looking at it from a Judaeo-Christian standpoint and say that I am paying for the sins of Adam and Eve, I am sorry, Vedanta doesn’t accept it. Vedanta says that each person is accountable for their action. I may have to bear the consequences of someone’s actions but I am not responsible for their actions. If a business I am a part of has cheated, I may have some debts to repay, but I am not considered a criminal unless I have acted criminally. That is where we differ from the Judaeo-Christian ethic, we don’t have the concept of ‘original sin’. Probably that’s where your question came up.