A little boy passes by while Jehovah's Witnesses discuss the Bible in Rostov-on-Don, Russia, in 2015. (Alexander Aksakov/For The Washington Post)

IN HER chilling memoir of Stalin’s Great Terror, Eugenia Ginzburg wrote of the trepidation she felt at night, when “enemies of the people” were often carted off by the secret police. “The windows of our bedroom faced the street and cars drove past all the time,” she wrote. “And how we listened in fear and trembling when it seemed as though one of them might be pulling up in front of our house.” That was 1937.

Now, more than seven decades later, midnight knocks on the door are being heard again in arrests of Jehovah’s Witnesses. Last year, the Russian Supreme Court declared the group “extremist ” and banned it from operating on Russian territory. There are 175,000 people professing the faith in Russia today. They report that 17 members are being held in pretrial detention in 11 regions. The arrest “always happens in the evening or at night when people are sleeping and the effect of surprise is most effective,” Yaroslav Sivulsky, a member of the European Association of Jehovah’s Christian Witnesses, told Radio Free Europe/Radio Liberty. “Sometimes security forces have discovered ahead of time where small gatherings of friends are being held, literally three to five people. Apparently, their telephones are being monitored or they are being followed.”

On May 30, officers of the Federal Security Service, known as the FSB, a successor to the Soviet KGB, knocked on the door of Tatyana and Konstantin Petrov in Magadan, in the Far East. A woman’s voice said the electric company needed to read the meter. When Mr. Petrov opened the door, officers rushed in, wrestled him to the floor and took him away. On June 14, a Magadan court confirmed Mr. Petrov’s detention on charges of “fomenting hatred or enmity on the basis of sex, race, nationality or religion.” Ms. Petrova said they had helped organize a Jehovah’s Witnesses gathering in a local hotel. “As usual at those meetings, we discussed the Bible,” she said. “That is the crime that they are accusing my husband of.”

Ms. Petrova is one of at least 10 wives of those arrested who have written an anguished open letter to President Vladi­mir Putin’s Council for the Development of Civil Society and Human Rights, “a cry of desperation,” as they put it, warning: “A campaign of terror has been unleashed against an entire religion, one of the largest Christian religions in Russia.” They write that investigators are demanding that members disavow their faith — or face prosecution. “But we cannot stop believing in God.”

The Jehovah’s Witnesses are not extremists. They refuse subservience to the state; they refuse military service, do not vote and view God as the only true leader. Now, as in Soviet times, they are victims of Mr. Putin’s authoritarianism. As the World Cup captivates spectators around the globe with stadium matches in the Russian provinces, it is important to remember that, under the cover of darkness, people are being arrested and jailed for reading the Bible.