[2][3] His movements first came about after starting out as simple retreats designed for both altar servers and families that later began to address a series of issues in Poland at the time.

In September 1939 he participated in the campaign to fight against the invading German armed forces at the outbreak of World War II.

[2] But his involvement in this campaign led to the Gestapo arresting him on 24 June 1940 that saw an investigation and Blachnicki thrown into the notorious German Auschwitz concentration camp as prisoner 1201.

[2] But something profound happened to him in his cell on 17 June 1942: he experienced a sudden conversion of faith in God in which he felt closer to Him and decided to dedicate his life to Him.

[3] He received his solemn ordination to the priesthood on 25 June 1950 in the Saints Peter and Paul church in Katowice from Bishop Stanisław Adamski.

This prompted him to work for a secret underground diocesan curia which put him into conflict with the diocese's vicar capitular Jan Piskorz.

On 8 September 1957 he began a national anti-smoking and anti-drinking campaign that was later named as the "Crusade of Temperance" on 10 August 1958; this work encouraged abstinence which could be offered to God as expiation for those addicted to drinking.

Blachnicki left for Rome on 10 December 1981 to help the Servant of God Luigi Giussani work on the Congress of the Renewal Movements but could not return to Poland due to the imposition of martial law.

In October 2020 with the agreement of the Church, his body was exhumed by the Institute of National Remembrance to allow a forensic autopsy.

In March 2023, Minister of Justice and Public Prosecutor General Zbigniew Ziobro announced that Blachnick's death was caused by a further unspecified toxin, confirming that he died of a poisoning.

[5] The decisive moment for the process came on 30 September 2015 after he was named as Venerable after Pope Francis recognized that Blachnicki had lived a model Christian life of heroic virtue.