The exact date of his ordination to the priesthood is not known, but the earliest notice of him in that connexion is in 1610 when he is mentioned by Andrés de Claramonte y Corroy in his "Letanía Moral", as Padre Fray Gabriel Téllez of the order of Nuestra Señora de la Merced. From Herbermann, Charles, ed. (1913). "Gabriel Téllez". Catholic Encyclopedia. New York: Robert Appleton Company.