"The path I followed was dictated by the human rights violations perpetrated against Palestine," he told the judges during his latest appeal for release.
Wounded in 1978 during Israel's invasion of Lebanon, Abdallah, a secondary school teacher, joined the Marxist-Leninist PFLP, which carried out a series of plane hijackings during the 1960s and 1970s.
A year later, Abdallah, along with his brothers and cousins, founded his own pro-Palestine armed group, the Lebanese Armed Revolutionary Factions (LARF). The group had contact with other far-left armed outfits, including France's Action Directe, Italy's Red Brigades and the German Red Army Faction (RAF).
The Lebanese anti-Israeli Marxist group claimed responsibility for five attacks, including four in France in 1981 and 1982.