His family moved to Latvia, where the former chaplain worked on the railroad. Lenga spent his one-year novitiate in the Marian Order, then a week visiting a monk, his spiritual mentor. From Latvia, he moved to Kaunas, Lithuania where there was one of only two Catholic seminaries in the then Soviet Union. He secretly graduated from the seminary, and was ordained in secret on May 28, 1980 by Bishop Vincentas Sladkevicius. In 1981, he arrived in Kazakhstan, where he performed pastoral ministry for 10 years. Lenga was appointed Apostolic Administrator of Kazakhstan and Central Asia, and Titular Bishop of Arba on April 13, 1991. He was consecrated a bishop on May 28, 1991. Lenga was next appointed bishop of Karaganda on August 6, 1999. He received the personal title of Archbishop on May 17, 2003. On February 5, 2011 Pope Benedict XVI accepted the resignation of Lenga, which he admittedly filed in accord with canon 401 § 2 of the Code of Canon Law. Diocesan bishops, who due to ill health or some other compelling reason is not fully be able to perform their duties, are urged to submit their resignation. However, Archbishop Lenga denies ever filing such a resignation. Lenga was appointed as the successor to the apostolic administrator of Atyrau, Bishop Janusz Kaleta. At this time, the retired archbishop was a resident of the monastic house ofthe Congregation of priests.
Declaration of Truths
On June 10, 2019, Lenga and four other bishops and cardinals published a 40-point "Declaration of Truths" claiming to reaffirm traditional Church teaching. The bishops wrote that such a declaration was necessary in a time of "almost universal doctrinal confusion and disorientation." Specific passages in the declaration implicitly relate to several writings by Pope Francis. The declaration states that "the religion born of faith in Jesus Christ" is the "only religion positively willed by God," seemingly alluding to a document signed by Pope Francis on February 4 called "Human Fraternity" which stated that the "diversity of religions" is "willed by God." Following recent changes to the Catechism to oppose capital punishment, the declaration states that the Church "did not err" in teaching that civil authorities may "lawfully exercise capital punishment" when it is "truly necessary" and to preserve the "just order of societies."