Tropes were chants in dialogue form introduced at certain moments in the liturgy for the Christmas and Epiphany masses to make them livelier and more understandable for the faithful.
Tropes were gradually transformed into dramas or liturgical plays and took on such spectacular and sacrilegious developments in their depiction of biblical scenes that the Church gradually eliminated them little by little from the liturgy and banned them from churches, relegating them to the church porch.