Diptych/Díptico is the first bilingual poetry collection of prize-winning poet Gilbert Luis R. Centina III. It consists of over one hundred poems in both English and Spanish. It is his contribution to the resurgent efforts to promote and revive the Spanish language as a lengua franca in the Philippines. Since much of over three hundred years of Philippine history is written in Spanish, he believes it holds the key to Philippine national identity. In this book, he pens some of the most damning verses written by a Roman Catholic priest against clerical abuses in line with his anti-clericalism advocacy. The artworks of Spanish multimedia artist Vicente Jáuregui are featured throughout the book, along with a single work of the author's sister, Louella Centina Garnado. Introducing the book is Spanish poet Antonio Aguirre and writing the prologue and the epilogue, respectively, are Spanish author Josemaría Alonso Alonso de Linaje and Spanish editor and educator Ana Maria Romo de Miguel. Foremost Filipino writer in Spanish Guillermo Gómez Rivera praises the Asian American author as a poet who "remains a Filipino at heart" by advancing the Hispanic roots of the Philippines through this bilingual collection.