Why is Primacy of Conscience taught and what degree of certainty is it in the Catholic Church?

I have collected various Catholic editorial headlines about this… *“The Catholic Church has always held to the primacy of conscience and taught that individuals must follow their consciences even when they are wrong…you should always follow your conscience.... Pope Francis on Saturday reaffirmed the “primacy” of using one's conscience to navigate tough moral questions in his ….Conscience takes priority over church teaching…Both the natural law and the Church have always upheld the moral necessity for each person to act in accordance with the dictates of his or her conscience.. 'It is never wrong to follow the convictions one has arrived at—in fact, one must do so.”* I do not understand this teaching. What Biblical or Catholic Tradition or natural law demands this teaching? The Catechism (#1782) and references to some Encyclicals seem to just repeat each other without a firm basis for this teaching. It seems counter intuitive and against right reason that everybody MUST do whatever they think is right despite a misinformed conscience, an erroneous conscience, a lax conscience, a dead conscience, and more. I understand the teaching that conscience should be formed rightly but how can Primacy of conscience be justified (even when wrong) above obeying certain teaching of the Catholic Church? I am not interested in theologians opinions, I am looking for firm and definitive teaching of Biblical, unanimous Church Tradition or natural law.