The history of the Brotherhood of the Clerics dates back to the year 1642, when the Fraternity of Our Lady of Poor Clerics was established in the city of Porto in 1654, at the building of the Brotherhood of St. Peter ad Vincula, and in 1666, at the foundation of the Congregation of St. Philip Néri.
The seat of the three Brotherhoods was at the Church of Mercy and despite their differences, their mission was to help members of the clergy in situations of sickness, poverty and death. Resolute in maintaining this mission, and ensuring the survival of the brotherhoods, which depended on the number of clerics and on financial stability, they decided to merge the brotherhoods.
On April 18, 1707, it was decided to establish the Fraternity of Our Lady of Mercy, St. Peter ad Vincula and St. Philip Neri, now called Brotherhood of the Clerics. Later, new statutes were created, a coat of arms was created to identify the Brotherhood, its assets and documents, and in the year 1731, it was decided that a proper structure should be built (church), since the new Brotherhood continued to gather at the Church Of Mercy. As a result, from the union of these three fraternities, the coat of arms combines the monogram of Mary (AM), the keys and the papal tiara of St. Peter, and the lily of St. Philip Néri.
On March 28, 1748, the Fraternity of Our Lady of Mercy, St. Peter ad Vincula and St. Philip Néri, definitively moved to its headquarters: the Church of the Clerics.