In the spring of 1789, Verlooy founded with Jan Frans Vonck the secret society "Pro Aris et Focis" (for Altar and Hearth), in order to prepare a rebellion against the emperor. In the fall of 1789 he became a member of the "Committee of Brussels" of the "Democrats" (with J.J. Torfs, Pieter Emmanual de Lausnay, J.Bpt.D. 't Kint, A. Daubremez, C.A. Fisco and De Noter). In fact, it is Verlooy who made the proposal to Vonck to organise a secret society with the name "Pro Aris et Focis" tasked with the liberation of the "Belgian" provinces from Austrian Habsburg despotism. They would simultaneously organise the rebellion in the cities and the emigration of patriots who would create an army willing to invade the homeland, which would also be the sign for a general revolt. Verlooy justified his intentions in a Dutch pamphlet and gave an explanation of his project: “three million Belgians suffer slavery... among them not less than 700.000 are fit enough to fight and are dissatisfied; ... one could easily find 300.000 people willing to risk their goods and their blood for their homeland. But in the same way as a prison guard is able to easily keep 200.000 prisoners in control - as they are locked up in isolation - a small number of soldiers - hardly 13.000 of them - separate us and keep us in slavery.” Vonck translated the regulations of the society into French, as they had first been drawn up in Dutch, and made them commonly known in all Walloon towns and cities. Thus, the initiative of Vonck and Verlooy led from a speechless but profound irritation and isolated riots to an overt and organised revolution.