During the Gaza war this year, Schmuel Kaufman, a military rabbi from a West Bank settlement, used to stride between the Israeli soldiers’ tents and urge them to fight what he deemed an “obligatory war” ordained by ancient scripture.

“It’s a holy war to protect women and children from the south of the country after a long period of endurance on our side,” he told The Times. “The commander of the battalion asked me to blow the shofar [a ram’s horn] every time before going into the fighting. I’m blowing the shofar while 500 soldiers stand behind me praying. They went in wrapped in holiness.”

Rabbi Kaufman and many other religious soldiers attributed Israel’s very low casualty rate in the month-long conflict to the newfound religiosity of its Armed Forces. In recent years, the army has become more devout, with an increasing number of recruits from religious and nationalist groups, including settlers.

Even secular professional soldiers, who long formed the backbone of the Israeli Army, admire the motivation and zeal of their nationalist-religious comrades, and say that they were some of the most effective fighters in Gaza.

But anti-settlement groups, such as Peace Now, warn that the national-religious movement has now become so strong in the military that no future government will dare to use the army in evacuating the increasing number of settler outposts that have sprung up across the West Bank, which they say explains the reluctance of the Ehud Barak, the Labour Defence Minister, to take such a politically explosive task.

One religious paratrooper who fought in Gaza and who asked to be identified only as Ilan, said that leaders of religious and settler communities encouraged their young people to join the army and to work their way up the ranks. The new recruits attend special pre-military seminaries, known as hesder yeshivas, to prepare them for army service. Most of these are in the occupied West Bank, which Israelis call Judea and Samaria.

Elyakim Haetzni, a founder of the large Kiryat Arba settlement in Hebron, said that the growing influence of the religious Right in the army was not a deliberate policy but a natural phenomenon, as the country becomes increasingly nationalist. Traditionally, elite combat units were drawn from members of the kibbutzim, the collective farms that formed the nucleus of the state of Israel at its birth in 1948 and which continued to hold sway until the 1980s.

The decline of kibbutz-based socialism in Israel coincided with the rise of religious nationalism after the 1967 Six Day War and the capture of Jerusalem – a sign to many religious Jews and their millions of Christian Evangelist supporters in America of divine intervention and the fulfilment of biblical prophecy. Gone are the days when religious Israelis confined themselves to scriptural studies and the spiritual safeguarding of the homeland. Now they sign up and fight.

When Rabbi Kaufman left the Israeli Air Force in 1966 there were only half a dozen religious soldiers in his unit. Today, there are 150. During the Gaza war, he said, prayer shawls were in high demand, even among otherwise secular troops.

"Today religious soldiers make about 40 to 50 per cent of the soldiers in the army. Many of them hold high ranks. This is thanks to the approach set forward by Rabbi [Avraham] Kook, the spiritual father of the national religious camp,” he said, referring to the early-20th-century religious leader who fused Zionist nationalism with religious teachings. His philosophy has had a profound effect on the religious settlers now building unauthorised outposts across the West Bank.

“Following Rabbi Kook's approach, hesder yeshivas and the pre-military colleges encouraged their students to go to combat units in the army, and aspire for high rankings,” he said.

In 2007, the army jailed 12 religious soldiers who refused to participate in the eviction of Jewish settlers who were illegally occupying buildings in the mainly Palestinian city of Hebron. General Gadi Shamni, head of the central army command at the time, said: "This is a dangerous phenomenon that threatens the very basis of the army being the people's army in a democratic state."

During the recent Gaza war, the army reprimanded some military rabbis for inciting soldiers to draw comparisons between the Palestinians and the Philistines, a long-defunct biblical civilization that fought the ancient Israelites and from which the modern name of Palestine descends.

Although the army spokesman's office denies any increasing influence of the national-religious, the military has already had to deal with stinging blows to its ability to operate in the occupied territories. In 2008, the army jailed 12 religious soldiers who refused to participate in the eviction of Jewish settlers illegally occupying buildings in the mainly Palestinian city of Hebron.

Mr Haetzni, the veteran settler leader in Hebron, said that any attempt to remove hundreds of thousands of Jewish settlers now living in the West Bank would result in a civil war. “General Jim Jones [the US national security advisor formerly in charge of training Palestinian security forces] will have to send in Nato forces, the American Marines,” he said.

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