Is a heresy good or bad?

Those who would proclaim something as "heresy" would be saying that it is something bad. Heresy is when a person's beliefs conflict with the generally accepted opinion (often Christian beliefs). Like if a person were to say to a priest "There is no god" or "I believe in evolution" or "Jesus was not the son of god" the priest would proclaim that the statement was heresy. But if the person were to say the exact same thing to an atheist, the atheist would agree.