Adonyahu studied at a Seminar of Rabbanim in Budapest and was a member of the student union “Maccabea”. In June 1944 he joined the movement’s underground activities under the fictitious name of Dunka László. Adonyahu went to Debrecen in order to take his family to Budapest since it was easier to hide in the capital city. However, except for one of his sisters, his family did not want to leave Debrecen.
Adonyahu traveled to Debrecen again twice with the same purpose until it was too late to save his family. He was caught but managed to escape and return to Budapest.
He distributed forged documents that arrived from the forgery laboratory of the Zionist youth movements underground and other sources thanks to David Grünwald (“Coca”) and supplied food to the bunkers.
He worked from the office of “Hanoar Hatzioni” which was located in the building of the International Red Cross on József Boulevard.
On October 15th, 1944, the day the Arrow Cross fascist party rose to power in Hungary, Adonyahu was caught in front of the “Glass House” on 29, Vadász Street while holding a bag full of documents. He was taken to the Gestapo headquarters on Svábhegy Hill and brutally beaten but he argued that he was only a messenger. From the Gestapo headquarters he was taken to the Toloncház prison.
Adonyahu was freed thanks to a safe pass given to him by a lawyer for the Zionist movement, Dr. Beregi. After the liberation he continued with the rescue operations.
Adonyahu made aliya. He worked as a school headmaster and was also sent on an educational mission to South America.
He passed away in Jerusalem.