Before his arrival in New Spain, he had been Inquisitor of the Indies and alcalde mayor of Santo Domingo, with his residence on the island of Hispaniola.
To carry out these orders, Charles named Luis Ponce de León as judge of the residencia and governor of New Spain.
Aguilar was sent as visitador (inspector), specifically charged with investigating the religious topics that might come up in Cortés's residencia.
The day after his appointment, Aguilar named Gerónimo de Medina his associate in the government of the colony.
On December 1, 1526 Cortés, as captain-general of New Spain, announced some decrees that caused public friction between the two.
On January 7, 1527, Antonio Cordero became alguicil de campo (bailiff of the countryside), named by Aguilar.
The alguicil general had a voice and a vote in the municipal councils that governed the capital and other towns.