The Third Council of Lima was a council of the Roman Catholic Church in Lima, at the time the capital of the Spanish Viceroyalty of Peru. It was the most important of the three councils celebrated in Lima during the 16th century, since it definitively organized the Church in the Americas. It was summoned by Archbishop Toribio de Mogrovejo in 1581, and lasted between 15 August 1582 and 18 October 1583.
The Council dictated many regulations and principles, centered around the evangelization of the aboriginals and their fair treatment "not like slaves but as free men", as well as their education and instruction in European customs. It decreed that the indigenous languages must be used, and forbade the use of Latin and the exclusive use of Spanish. It produced a trilingual catechism (then known as "Catechism of St. Toribius"), in Spanish, Quechua and Aymara. This catechism was later translated into the Guaraní language by Luis de Bolaños, and adopted by the First Synod of Asunción (1603) for use in the area of the Upper Paraná River basin (eastern Brazil, Paraguay and northeastern Argentina).
The Council also encouraged the establishment of seminaries. It set standards for the ordination of priests, forcing them to visit their congregations regularly, and for the appropriate use of liturgy to attract the natives to the celebrations.