Arte y bocabulario de la lengua achagua: Doctrina christiana, confessionario de uno y otro sexo e instrucción de cathecumenos (The art and vocabulary of the Achagua language: Christian doctrine, the confession of both sexes, and instruction in the catechism) attests to the linguistic effort undertaken by the Jesuit missionaries in the borderlands of present-day Colombia and Venezuela. As its long title explains, this small manuscript volume, written in beautiful calligraphy and now preserved in the National Library of Colombia, contains several items: a grammar of the Achagua language, an extensive vocabulary in which the Spanish equivalents are given for each Achagua word, instructions for confessors (with the translation of the interview to be given to new parishioners by the priest), and a catechism. The text stresses the importance of using the correct indigenous language, for it was only through this medium that it would be possible to Christianize the natives. The work was begun by Father Alonso de Neira, who died in 1703. It is uncertain whether it was simply transcribed by Father Juan Rivero, who arrived in the country in 1705, or further developed by him as he became expert in the language. Achagua is a language of the Maipurean Arawakan group traditionally spoken by the Achagua people of Venezuela and east-central Colombia.