It is part of our personality that helps you determine between right and wrong. It makes one feel guilty when he does something wrong and good when something kind. It ensures conformity with the value system of the individual.
Conscience is the subjective norm of morality in which we trace the moral authority inside the individual. It is not something that directs from outside. Conscience is an ‘inner voice’ as described by Mahatma Gandhi which directs one by telling
what to do or what not to do. Conscience can be defined as the subjective awareness of the moral quality of one’s own actions as indicated by the moral values to which one subscribes.
Conscience describes two things – what a person believes is right and how a person decides what is right. More than just ‘gut instinct’, our conscience is a ‘moral muscle’.
By informing us of our values and principles, it becomes the standard we use to judge whether or not our actions are ethical.
Acts of Conscience
The feeling of remorse has always been connected with conscience. It is a deep regret for a wrong committed. Conscience not only makes judgement over certain actions that we have done as right or wrong, but it arouses a peculiar feeling of pain that is extremely unpleasant. This pain of conscience or feeling of remorse is identified by moralists as one of the reasons of avoiding wrong actions.
(source: https://ethics.org.au/ethics-explainer-conscience/ )