Why am I an artifact

"Jace is a 10-year-old kid (at least for now) who ran away from the church after they decided to sell him because of his magic. While trying to find a place to stay, he meets an old man and strikes a deal to help him in exchange for shelter. Surprisingly, the old man turns out to be a legendary warrior from his prime - and a noble! Now, under the old man's strict discipline, Jace is forced to enroll in an academy."