formal definition in the 12th and 13th centuries

• How did St. Thomas Aquinas explain the nature of purgatory and the types of sins associated with it?


  State of being- venial sin (less serious sins)
• what was the significance of the Second Council of Lyon in 1274 for the doctrine of purgatory?


  declared middle state where souls are purified. Emphasised prayer in particular mass
• how did visionary literature, such as Dante's Divine Comedy, shape the medieval imagination of purgatory?


  it explained a mountain where souls ascended through levels of purification- descriptions of purgatory