Explain the contrapasso based on Dante's conception of heresy as the denial of the immortality of the?

"Dante opts for the most generic conception of heresy--the denial of the soul's immortality (Inf. 10.15)--perhaps in deference to spiritual and philosophical positions of specific characters he wishes to feature here, or perhaps for the opportunity to present an especially effective form of contrapasso: heretical souls eternally tormented in fiery tombs. More commonly, heresy in the Middle Ages was a product of acrimonious disputes over Christian doctrine, in particular the theologically correct ways of understanding the Trinity and Christ. Crusades were waged against "heretical sects," and individuals accused of other crimes or sins--e.g., witchcraft, usury, sodomy--were frequently labeled heretics as well.

Heresy, according to a theological argument based on the dividing of Jesus' tunic by Roman soldiers (Matthew 27:35), was traditionally viewed as an act of division, a symbolic laceration in the community of "true" believers. This may help explain why divisive, partisan politics is such a prominent theme in Dante's encounter with Farinata."