He was ordained to the priesthood by Bishop Verdon in St Joseph's Cathedral, Dunedin on 31 January 1904. Bishop Verdon placed a strong emphasis on Roman models and on devotion to the Holy See. Liston was deeply influenced by Verdon, who encouraged his vocation, sponsored his studies and was Liston's bishop for the first 14 years of his priesthood. He regarded Verdon as his ultimate role model and throughout his career kept a photograph of Verdon on his desk "for guidance through reflection on his way, and for seeking his heavenly intercession".