This question is a historical one that requires some context.
During the Spanish conquest of Mexico in the 16th century, Catholic priests arrived in the region and began to convert the indigenous people to Christianity. As part of this process, they often destroyed or burned indigenous religious texts and artifacts. This was done for a few reasons. Firstly, the priests believed that the indigenous religions were pagan and therefore evil. They saw it as their duty to destroy these religions and replace them with Christianity. Secondly, the priests believed that the indigenous texts contained false teachings and superstitions that could lead people away from the true faith.
Finally, the priests may have burned the texts simply because they did not understand them and saw them as a threat to their own authority.
It is important to note that the burning of these texts was a tragic loss of cultural heritage and knowledge. Many of these texts contained valuable information about indigenous history, religion, and culture. The destruction of these texts has made it difficult for scholars to fully understand and appreciate the richness of indigenous cultures in Mexico.
In summary, the Catholic priests burned sacred Mexican texts as part of their efforts to convert the indigenous people to Christianity and to eliminate what they saw as pagan and false teachings. However, this action resulted in the loss of valuable cultural heritage and knowledge.