The purpose of this article is to examine the ways in which Lope de Vega manipulates epistolas to serve his own ends with regards to language, both on a narrowly literary level and on a broader personal and even national one. What emerges is an epistola which blends both the self-evident art of poetry writing and critical speculation upon it, one which Lope consciously uses as a literary mode of vindication and defense for his ideas regarding proper discourse and as an attack on any type of discourse of which he disapproves.
Mascia, Mark. "Poetry as Theory: Lope de Vega's Epistola as Arbiter of Proper Discourse." Hispanic Journal 21.2 (2000): 481-499.