This paper examines personal letters and diaries of Egyptian Muslim Brotherhood volunteers who came to Palestine in 1948 to fight alongside Palestinians against the Zionist forces. The letters and diaries were found in June-July 1948 by Israeli soldiers in an abandoned armored vehicle in the village Bir ‘Asluj in the Negev\Naqab area. They were collected for the purpose of gathering military intelligence, and eventually made their way to the Israeli archives. The ties between the Society of Muslim Brothers and Palestine go back to the 1936 Arab revolt in Palestine when Hassan al-Banna launched a campaign in Egypt to support Palestinians. By 1938 al-Banna had declared that “jihad for Palestine” was an individual duty for every Muslim (fard ‘ayn), although it is unclear whether any of the society’s volunteers actually fought in Palestine during the revolt. A decade later in 1948, several hundred volunteers were drafted by the society in Egypt and sent to Palestine. They launched a few independent attacks against Jewish settlements before being integrated into the Egyptian army when it entered Palestine in May 1948. The volunteers’ letters give us unique access to what they were saying about who they were, what they were doing and why, thereby going beyond the official statements of the society’s leaders which have been used extensively by historians to tell the story of the Muslim Brothers. To better understand the sources of influence on volunteers, I will supplement the analysis of the letters with examination of the official Brotherhood line in regards to Palestine from 1946 to 1948, as portrayed in the society’s newspapers al-Ikhwan al-Muslimin and al-Shihāb. One of the key themes examined in the paper is the relationship these young men had with their parents, who objected to their decision to volunteer. Although they did not challenge the importance of fighting to save Palestine, many parents asked their sons not to act on what they saw as “youthful zeal” and abandon their studies. Some of the questions I seek to answer in the paper are whether these volunteers held different religious ideas than their parents, and to what extent their leaving their studies to go to Palestine was an act of rebellion.