How does Dante depict the level of suffering for the Heretics in Circle 6?

Dante depicts the level of suffering for the Heretics in Circle 6 through the imagery of them being burning in tombs. This vivid portrayal reflects the nature of their sins, which involve the denial of the afterlife and a rejection of faith. The fiery tombs symbolize both the punishment they endure and the eternal consequences of their beliefs. The Heretics are trapped in a state of anguish, as the flames that consume them symbolize their unending suffering for having rejected the divine truth. Additionally, the closed-off tombs illustrate their isolation and the permanence of their fate, reinforcing the severity of their heresy in Dante's moral framework. The suffering is not just physical but deeply tied to their spiritual state, emphasizing the gravity of their choices and the implications of their denial of God.