Boomkerk

On January 19, 1944, a requiem mass for Jan Verleun, a 24-year-old resistance fighter who had been executed on the Waalsdorpervlakte on January 4, took place here in this church, also known as the Tree Church. Verleun came from a Catholic family on Admiraal de Ruijterweg and had joined resistance group CS-6 after his military service, in which he was wounded in May 1940. He was involved in several acts of sabotage, including the liquidation of General H.A. Seyffardt, responsible for recruiting Dutchmen for the Waffen-SS.

The Mass was led by Father Van Houdt, and was sober. Afterwards, however, the organist played the song "I had a brother-in-arms, none braver than he...," a song often heard in Nazi Germany at funerals of Catholic soldiers. Although not intended as a tribute to the occupier, it was taken as a provocation by members of the National Socialist Movement (NSB).

On January 28, 1944, the NSB newspaper Volk en Vaderland sharply criticized the Mass and the closing song. That same day, Pastor Van den Bosch, Father Van Houdt and the organist were arrested by the Sicherheitsdienst (SD) and transferred to the prison in Scheveningen. They were released a few days later after interrogation in The Hague. The organist stated that he had only recently returned from Berlin and did not know that the mass was intended for Verleun; he had played the song out of habit.

Nevertheless, on February 28, 1944, Father Van den Bosch was permanently removed from his position by the SD and had to leave the province of North Holland. The diocese of Haarlem did not formally agree to this, but nevertheless appointed a temporary replacement on March 2, 1944: Father Van Houdt.

The situation ultimately appears to have been instigated primarily by local Catholic NSB members, who had previously criticized the pastor's attitude toward National Socialist parishioners. Although the German authorities did not formally follow up further, the incident led to the pastor's long-term removal and much unrest within the parish.