December 13, 1981 marked the beginning of the last stage for the life and work of Fr. Jerzy Popiełuszko. His first sermon under martial law was on January 17, 1982 when he encouraged people to think about those deprived of their liberty. Fr. Popiełuszko had delivered 26 sermons since the introduction of martial law. He discussed obvious aspects of life - the necessity of truth, honesty and love among the members of society. It was dangerous for the authorities because he was exposing the lies of the regime and the simplicity of his sermons clearly contrasted with the language of the party's propaganda. Notes one of the biographers: "Fr. Jerzy was a voice that could not be silenced" (Kotański, J.) He was also a very hard-working person. In addition to the Masses for the country, he initiated Nowa Huta workers' pilgrimage to the sanctuary of Jasna Góra. The idea soon evolved into a Nationwide Pilgrimage of the Working People.
The Communists could not accept Fr. Jerzy's activity just as they could not accept the truth and honesty he advocated. Communist security service began to come ever closer to the priest. Having been unable to exclude him from pastoral work by exerting pressure on his superiors, the Communists began to intimidate Fr. Jerzy. His apartment was broken into (twice), he was being constantly followed, his car was damaged and car crashes were arranged. In September 1983, public prosecutor Anna Jackowska started an investigation against Fr. Jerzy Popiełuszko and in December that year she charged him with the abuse of the freedom of conscience and religion to the detriment of Polish People's Republic. In the first half of 1984 he was arrested once and brought in for interrogation thirteen times. Driven by the security and propaganda services (notably by Jerzy Urban, the government spokesman, who referred to the sermons as "the sessions of hatred") organized attacks by the media and the press also intensified. Press conferences held by the government spokesman often could have been construed as instructions on how to deal with the rebellious priest. In view of the growing tension, many attempts were made to relocate Fr. Jerzy to Rome. However, he declined to study there "saying that: »I cannot leave these people, I cannot betray them".« To leave at that time would have meant to escape from the position the Church had trusted him with. He added: »I stayed through the difficult times and I am supposed to leave them now? What will the Church offer them - my resignation, my betrayal?« He cried. Nevertheless he was aware of the danger" - recalls Fr. Zdzisław Król.