131. Conscience is formed with a man of the Church through the truths of faith from the Word, or from the doctrine derived from the Word, according to their reception in the heart. For when a man is acquainted with the truths of faith, and apprehends them in his own way, and afterwards wills and does them, he receives conscience. Reception in the heart means reception in the will; for a man's will is what is called the heart. Hence, those who have conscience, say what they say from the heart, and do what they do from the heart. They also have an undivided mind, for they act according to what they understand and believe to be true and good.