He devoted most of his life to the evangelization of Black slaves arriving in the Colombian port city of Cartagena, and was the mentor of Saint Peter Claver.
[1] During his stay in Lima, he began to collect documentation and bibliography on Africa, compiling both accounts of ancient writers and studies of other Jesuit fathers.
During his stay in Lima, Sandoval began to write his work Naturaleza, policia sagrada y profana, costumbres y ritos, disciplina y catecismo evangélico de todos etíopes, which he completed in 1623.
In that treatise on evangelization in America with considerations on the indigenous peoples of Peru, Acosta posits that the success of the missionary depends on his capacity to be flexible, pragmatic and adaptable in his relations with future converts.
[2] De Instauranda is considered one of the most important texts for the ethnography of African slavery in Iberian America,[3] along with the works of the Portuguese Jesuits António Vieira (1608-1697) and Jorge Benci (1650-1708).