In this work we review certain biographical and historical data concerning Sor Juana and María Luisa, Condesa de Paredes. In addition, we have chosen Ovillejos 214, Romance 61, Redondillas 90 and 91 as poems that provides important insight into their relationship of patronage and friendship. In order to delineate theoretically both aspects of this relationship --the public and the personal-- we make use of the concept of ekphrasis proposed by Frederick de Armas. This concept is applied to the analysis of Romance 61, which is in the tradition of the lyrical Petrarchan portrait. Redondillas 90 and 91 are examined from the theoretical perspective of Cicero's amicitia, which serves to define an alternative model of feminine amicitia. In constructing this model, we review the written criticism surrounding María de Zayas' comedy, La traición en la amistad (1635). This criticism insists on a certain configuration of feminine friendship necessary for understanding the relationship between the two women. As is demonstrated in the analysis of the poems, the two women developed a mutual and permanent affection for one another until the death of Sor Juana in 1695. The Condesa de Paredes also provided practical support to Sor Juana for the publication of her first book, Inundación castálida (1689), which launched her to literary fame. To date there have been no critical studies that apply the concepts of ekphrasis and feminine friendship to the study of anecdotal clues found in the poems of Sor Juana for analyzing the nature of her relationship with the Condesa. This is the contribution of the present work.