(References are in chronological order and present some of the valuable expert literature on the subject.)

“The extent of loyalty toward the state was the criterion for initiating persecution. . . . The ‘International Association of Earnest Bible Students’ [and] the ‘Watchtower Bible and Tract Society’ were the first religious association to be hit by the Nazis, and they were hit the hardest. Hardly an analysis has been made, or any memoirs written about the concentration camps, which do not include a description of the strong faith, the diligence, the helpfulness, and the fanatical martyrdom of the Earnest Bible Students.”​—Kirchenkampf in Deutschland 1933-1945, by Friedrich Zipfel, Berlin, 1965, p. 175.

“It is striking that no other religious sect suffered as much under National Socialism as did the Earnest Bible Students.”​—Die Ernsten Bibelforscher im Dritten Reich, by Michael H. Kater, published in Vierteljahrshefte für Zeitgeschichte, April 1969, Stuttgart, 1969, p. 183.

“The distribution of the ‘Resolution’ [on December 12, 1936] and the ‘Open Letter’ [on June 20, 1937] were not only a very spectacular, but also a new way of public preaching . . . [These were] campaigns throughout the ‘Reich’ that were so well coordinated that they could take place all over Germany on the same day and at the same time. . . . Throughout the whole Nazi era in Germany, there was no other resistance organization that took comparable initiatives.”​—Widerstand “von unten.” Widerstand und Dissens aus den Reihen der Arbeiterbewegung und der Zeugen Jehovas in Lübeck und Schleswig-Holstein 1933-1945, by Elke Imberger, Neumünster, 1991, p. 345.

“As a totalitarian state, it required that people give their full devotion to the regime. The Hitler government had placed itself in the position of God and demanded that the entire ‘national community’ be in harmony with the Führer. And thus, resistance became a mandatory dictate of self-esteem and self-assertion for the religious denomination of Jehovah’s Witnesses.” Between Resistance & Martyrdom: Jehovah’s Witnesses in the Third Reich, by Prof. Dr. Detlef Garbe, Madison/​Wisconsin, 2008, page 528.

“As early as in the Weimar Republic, Jehovah’s Witnesses were exposed to the hostilities of racial-nationalistic forces, the church, and the first legal measures from the state. . . . Although in 1933 the IBV [International Bible Students Association] tried to adapt to the new situation and declared their strictly nonpolitical and anti-communist nature, harsh conflicts with the government agencies soon followed. Already the spring of 1933 saw heavy persecution, confiscations, and bans of publishing, preaching, and organizing.”​—Widerstand und Emigration. Das NS-Regime und seine Gegner, by Hartmut Mehringer, Munich, 1997, paperback edition, 1998, p. 103.

“The first thing we can learn from the attitude of Jehovah’s Witnesses in Nazi Germany is that a small group, relying on their faith and resolute solidarity, succeeded in withdrawing from the Nazi regime’s totalitarian grasp, albeit at a high price. . . . Second, it should be an obligation for us, the generations born after the Third Reich, to ensure that people will never again have to die to remain true to their conscience.” The Religious Association of Jehovah’s Witnesses in Baden and Wurttemberg, 1933–1945, by Dr. Hubert Roser, in: Dr. Hans Hesse (ed.), Persecution and Resistance of Jehovah’s Witnesses During the Nazi Regime 1933–1945, Bremen 2001, page 207.