St. Thomas Becket disagreed with King Henry II about the position of the Catholic Church in 12th century England.
He said the Church has absolute power in ecclesiastic affairs and the English king said he had the right to command Bishops and faithful. This is the error of Regalism.
St. Thomas disagreed and was exiled. Upon his return, he attacked these errors and was murdered in the sanctuary of Canterbury Cathedral where he was Archbishop.
Although many English went to the death site to honor the slain Bishop, the nobles and clergy still supported Regalism.
Over time, this laid the groundwork for the Protestant Revolt of King Henry VIII and Anglicanism. The hatred for St. Thomas and the Catholic Church was so great that 400 years later, Henry VIII burned his relics to erase his memory.
St. Thomas’ second martyrdom -- a martyrdom that gave him the glory of being hated by evil for Christ's sake. His fidelity was so great he was considered a threat 400 years later.
Think of the action of a termite on wood. The termite eats the interior of the wood leaving the exterior intact. With time, the interior grows weak. The entire edifice collapses. Apply the same principle to the Catholic Church. Bad doctrines within will weaken the entire orthodox structure over time.
St. Thomas’ life helps us understand what can happen when error goes unopposed. May Our Lady stop the errors of today and bring about the glorious reign She promised at Fatima, the triumph of Her Immaculate Heart in the world.