Jacques Johan Cornelis Terwisscha van Scheltinga worked as a salesman in a clothing store in Dokkum, was to be deported to Germany for forced labor, but escaped at the train station in Leeuwarden and went into hiding with his uncle in Weert.
The director of the regional employment office in Weert wrote on November 15, 1952:
He was registered as employed by the Nederlandse Heide Maatschappij as of 21.9.1943 in order to be able to issue to this person a so-called "AUSWEIS". [1#10]
In Weert he came into contact with the priest and geography teacher Charles V.J. Brummans, who worked at the Episcopal College in Weert and (who works with the escape organization Luctor et Emergo, an organization that considers its mission to hide and transport prisoners of war, as well as to bring crashed airmen on their way back to Allied territory. 
The name Luctor et Emergo means: I go under and come up again. This is also the heraldic motto of the province of Zeeland. Perhaps this was confusing. In any case, it was changed to Fiat Libertas (Let there be freedom) in April 1943. About this group we read:
The resistance group Luctor et Emergo was founded in 1942 with the main goal of spying for the government in London.
…In September 1943, the resistance group was gradually busted. [3.1]
The most detailed information about him can be found on the oorlogsbronnen.nl website about the war memorial in Dokkum. Other sources sometimes have verbatim the same text about Jacques, but less detailed. Quote:
He did his first illegal work on July 8, 1943, when he brought an Allied pilot to Belgium. After several arrests and escapes, he was arrested again on November 7, 1943 by betrayal.etrayal. This time in the house of his friends, the Breukers family in Weert. This time escape was impossible. Via Haaren in North Brabant, he arrived at the prison on the Gansstraat in Utrecht. Jacques was sentenced to 20 years in prison. Via Recklinghausen and Hameln he was put to work in the salt mines of Celle. He died on April 11, 1945 and was buried in the Waldfriedhof (forest cemetery) in Celle. 
The death certificate from the civil registry in Celle gives the address Trift 14 as the place of his death. That is still the location of the prison today. [1#11]
What happened to his remains afterwards is a mystery. There was probably complete chaos when the war dead were reburied in the Waldfriedhof cemetery, despite authorities’ claims to the contrary. [1#19 et seq.]
From the biography of his resistance colleague Tjeu Beelen: Only toward the end of 1943, when the organization had been decimated by infiltration and betrayal, did a separation occur between the two activities. Intelligence work was placed under the so-called Swiss Way B and pilot assistance came under the wing of the L.O. 
For this reason, and because there are only two members of Luctor et Emergo on this website, Jacques is listed here as a LO member. See also Oscar Wolters.
Willem Terwisscha van Scheltinga assumes that his uncle died in the Bergen-Belsen concentration camp 25 km away. This differs from the other sources:
Arrested by Sipo 7 November 1943. Sentenced with 21 persons involved in Luctor et Emergo. Jacques got 6 years and died in Celle – Bergen Belsen a week before the concentration camp was liberated. [3.2]
According to oorlogsgravenstichting.nl no grave was found in Celle, but nevertheless the grave number 3-1205 is given there. 
A marble plaque in the Rumoldus Chapel in Weert bears his name, among others. 
He is listed in the “Erelijst 1940-1945” (Honor Roll of the Dutch Parliament).