Israeli soldiers are sometimes ordered to evacuate West Bank settlements
About 200 Israeli teenagers have pledged to disobey any orders to evacuate Jewish settlements during their military service.
The letter sent to Defence Minister Ehud Barak was signed by young people about to be drafted into the Israeli Defence Force.
Jewish law as written in the Torah forbids the dismantling of Jewish-built homes, the letter said.
The government has ordered a 10-month lull in building in the West Bank.
"We consider utilizing the army for political ends and for warfare against Jews an existential danger and a destruction of the military," the letter said.
"We pledge our loyalty to the Torah precedes any law or order, and therefore we will refuse to execute any order that contradicts the Torah, and will not take part in the evacuation of any outpost or settlement in the land of Israel, and thus also guarding the true values of the IDF," said the letter, printed in the Jerusalem Post.
Mr Barak has said the military will break its ties with Jewish Talmudic academies, or yeshiva, which tell their students to disobey orders during their military service.
The Israeli military and about 40 Jewish seminaries have a decades-old arrangement, known in Hebrew as "Hesder", that allows observant Jewish men to combine military service and religious studies.
Religious Jews see the West Bank as part of the Holy Land, given to them by God.
Earlier this year, Israeli reservists signed a petition requesting exemption from Jewish settlement evacuations.
In October, a group of soldiers disrupted their swearing-in ceremony in Jerusalem, calling for continued Jewish settlement in the West Bank.
All settlements built on land occupied by Israel since 1967 are illegal under international law.
Close to 500,000 Jews live in more than 100 settlements built on occupied territory since 1967.
Israel disputes the international law on this issue, but does deem those settlements built without Israeli government permits as illegal and from time to time instructs its soldiers and military police to evacuate them.