“In the depths of our conscience, we detect a law which does not impose, but which holds us to obedience. Always summoning us to love good and avoid evil, the voice of conscience when necessary speaks to our heart: do this; shun that. For we have in our heart a law written by God; to obey it is the very dignity of being human; according to it we will be judged” (Gauidium et Spes paragraph 16) from Vatican II.
We have that inner voice that tells us what is good and evil and to follow God in it all. The question is do we listen to it? If we do hear it do we follow what is good?