Born in Tel Aviv, Stern attended Bar-Ilan University, where he received a BA in Economics and Land of Israel Studies. He also received a Master's degree in Business Administration from Tel Aviv University and Northwestern University. Stern was drafted into the IDF in 1974. He volunteered as a paratrooper in the Paratroopers Brigade. He served as a soldier and a squad leader. In 1976, he became an infantry officer after completing Officer Candidate School and return to the Paratroopers Brigade as a platoon leader. Stern took part in various raids against terrorist camps in Lebanon, and served as a Company commander in the 890 "Efe" paratroop company. Stern fought in the 1982 Lebanon War, and later on commanded Paratroopers Brigade's training base and the 202 paratroop battalion in South Lebanon. During his career, Stern commanded a reserve Paratroopers Brigade and the IDF's Officer Candidate School. Afterwards, he served as the chief of the IDF's Education and Youth Corps and succeeded Gil Regev as head of the Manpower Directorate in July 2004. As head of Human Resources, Stern oversaw a program to convert non-Jewish IDF troops to Judaism. He has also led the integration of hesder units, homogeneous units of Orthodox male soldiers combining yeshiva studies with military service, into mainstream units. While criticised by some religious Israelis that the action was meant only to prevent insubordination of religious troops during the Gaza pullout, Stern maintains that it is better for the troops. On 14 October 2005, Stern and his family were assaulted in Jerusalem while praying at the Western Wall in protest of his leading role in expelling Jews from the Gaza Strip during the disengagement plan. In 2008, he is said to have "stormed the stage" to prevent teenage rock star Shira Gavrielov from performing at a military farewell party on the grounds that she had not served in the military. Stern completed his tenure as the head of the Human Resources Directorate in July 2008, and retired from the IDF. He was replaced by Avi Zamir, who received the Aluf rank. Prior to the 2013 Knesset elections, Stern joined the new Hatnuah party, and was placed fourth on its list. He was elected to the Knesset after the party won six seats, but announced on 20 December 2014 that he had left the party. In the build-up to the 2015 elections, he joined Yesh Atid, and was placed twelfth on its list. With the party winning only 11 seats, he lost his seat. However, he re-entered the Knesset on 4 September 2015 after Shai Piron resigned his seat.
