The Israeli Supreme Court ordered a temporary suspension of work on a new Jewish settlement on the occupied WestBank of the Jordan River yesterday, the second such injuction in favor of West Bank Arab landowners in four months.

The court ordered that construction on the government-approved project be stopped immediately, and that Defense Minister Ezer Weizman and the West Bank military commander, Maj. Gen. Avraham Orli, explain why all civilian settlement activity at the Beit El site should not be halted permanently.

Coming on the heels of a similar restraining order issued May 25 against a government-approved settlement at Nebi Salah, like Beit El near the town of Ramallah, yesterday's decision was viewed by West Bank Arabs as victory in their campaign against expropriation of private property for civilian settlements.

The decision also came at a time when West Bank Palestinians and liberal Israelis have been expressing increasing frustration over Israel's unclear policies on land acquisition in the occupied territories, and at a time when the disclosure of positions taken at the Camp David summit are expected to focus attention again on the West Bank settlement issue.

Followers of the Gush Emunim, or Faith Bloc. the ultranationalist group that has vowed to build Jewish settlements on the West Bank until Palestinians are a minority, assailed the court order and said it has "grave repercussions" for settlers in territories occupied during the 1967 war.

The Supreme Court yesterday was sitting as the High Court of Justice, a judicial body that reviews government actions and determines whether they are consistent with the law.

Under the Hague Convection and the fourth Geneva Convention, an occupying power can sieze private property for military purposes, but not for civilian settlement. At Beit El, as in numerous other settlements here, the site originally was acquired as a para-military nahal and then transformed into a civilian Jewish settlement.

Supporters of the 12 Arab landowners whose property is involved said that in December 1977 ground was broken for the first 20 concrete prefabricated houses within the perimeter of an adjacent military training base.

Because the activity was inside the base, a former Jordanian Army facility, no complaint was issured, they said. Villagers said, However, that last month they began noticing construction of housing units outside the perimeter on private property expropriated in 1970 for solely military purposes.

Last week, the West Bank residents said, they noticed the nucleus of a Gush Emunim settlement move out of temporary quarters on the army base and into the unfinished buildings.

The West Bank Arabs claimed the relocation was speeded up when the landowners filed notice of their intention to sue, and that the Jewish Agency was ordered to speed up work. According to plans, 90 house and a religious study school were to have been built on the site.

The Supreme Court yesterday ordered the government to explain within 40 days why the army should not be permanently enjoined from erecting buildings at the site for civilians, and why local Palestinians should not be allowed to inhabit the buildings.

The court issued its order after only one day of testimony, apparently acting so quickly because there was little question of proof of ownership. Deeds and maps showing ownership of all the parcels in the approximately 15-acre site were submitted and all the owners live in the area, thereby eliminating complications involved in absentee owner cases.