The core of human freedom is the moral conscience.  The conscience is constituted of all the human faculties, and is therefore considered the heart of the human person.  It is where the human person meets the Truth, Beauty and Goodness that is God.  Thanks to the moral conscience, we are able determine our character and our ultimate destiny.  However, we must be careful stewards of our conscience, for if it is poorly formed it can lead us away from the goodness that God intended our lives to be.
The moral conscience is the power to use reason to apply the moral law to specific situations.  It is based on the objective truth about the moral law.  In fact, the word “con-science” has knowledge of objective truth at its etymological root. 
At the same time that it relates to objective truth, the conscience is also intensely personal.  The conscience resides in the heart of the human person – the deepest recesses of our being.  It is constituted of all of the human faculties.  The intellect empowers us to know the moral law and to reason out how to apply it to specific situations.  The will empowers us to choose according to our conscience rather than being led by our passions.  Thanks to our sense appetite, we experience emotional reactions in response to the movement of our conscience.  We experience guilt when we judge our actions as evil.  We experience peace or joy when we judge our actions as good.  The involvement of all of our faculties is one way to understand that the conscience is in the human heart.

Examination of conscience and self-determination

We also use this ability to reason about good and evil to examine our past actions and judge them.  This power of intellect and free will ultimately allows us to form our character and decide who we are to become.  When we identify an action as good or evil, we can decide if we want that action to become part of who we are (by repeating the act and making it a habit) or if we are going to conquer that evil by avoiding temptation to that act in the future or refusing to repeat the action.  Each moral choice we make shapes our heart toward Goodness or away from it so that, ultimately, our final destiny will be decided during our final judgment when we ultimately choose God, the source of Goodness, or choose against Him.

God speaks to the heart through the conscience

Of course, our ultimate destiny is not made without Divine help.  Without grace, relationship with God would be impossible in the first place.  Additionally, all of our moral choices are made in the context of our relationship with God.  In addition to the spark of