A polarized Israel debates an apparent rise in 'Jewish terror'

A foiled grenade attack on Islam's third holiest shrine inside the ancient walled town of Jerusalem has sparked alarm among Jews and Arabs alike over the threat of apparently ''Jewish terror'' in an increasingly polarized Israel.

Sunday morning the Israeli mayor of Jerusalem, Teddy Kollek, paid a condolence call on the city's Islamic mufti. Mr. Kollek has been a vocal critic of the Israeli government's reply to nearly 15 similiar incidents at non-Jewish sites since late last year, saying recently: ''Not everyone in the government seems to be taking this matter seriously.''

The attacks have caused several injuries.

Before dawn on Friday, Islam's holy day, Arab guards spotted two men scaling old Jerusalem's stonewall near the octagonal mosque known as the Dome of the Rock. The site is revered by Jews and Christians as the spot where Abraham had intended to sacrfice his son, Isaac. But it is especially revered by Muslims, who believe the prophet Mohammed rode a steed to heaven there.

The guards summoned Israeli police, who, though unable to snare the intruders , found a 10-pound package of explo-sives and 18 Israeli Army-issue grenades.

Saturday, police detained two men at a Bible lesson led by Rabbi Meir Kahane - an American-born Israeli and militant campaigner for unfettered Israeli control of the Holy Land. At time of writing, it was unclear whether the men would be charged in connection with the bomb attempt.

The Israeli government, which had drawn fire from the opposition for an allegedly relaxed response to earlier incidents, energetically condemned Friday's attempted attack. Interior Minister Yosef Burg, the minister responsible for the police, said the incident ''contravened the basic principles of the state.'' He vowed to ''spare no effort in catching the culprits.''

Who these culprits are, officials stress, remains to be determined. The government has so far been reluctant, as one local newspaper puts it, to speak the words ''Jewish underground'' in connection with the attacks on local Christian and Islamic sites or offices. The Israeli media have been less circumspect, assuming a minority of extremist Jews are likely culprits.

Telephone callers identifying themselves as members of a group named TNT - the Hebrew abbreviation for ''Terror vs. Terror'' - have claimed responsibility for the attacks. They claim to be responding to violence against Israelis by local Palestinians. Rabbi Kahane was briefly detained in early January after having implied endorsement of TNT.

The Jerusalem incidents seem the latest offshoot of a process of political polarization in Israel - and the Israeli-occupied West Bank of the Jordan - in recent years. Fueled by controversial issues like Jewish settlement of the West Bank and the war in Lebanon, the process involves tension both between Jew and Arab, and among Israeli Jews themselves.

On the West Bank, the result has been a serious of shootings and other violent acts involving Jewish settlers and local Arabs - including the recent killing of a Palestinian girl in the area's largest Arab town, Nablus. Two days ago, a pair of Jewish settlers was charged in the shooting, which had followed a Nablus demonstration in which stones were hurled at Israeli vehicles and a presumably Palestinian bomb attack on a Jerusalem bus in which four Israeli civilians, including two children, were killed.

The Lebanon dispute led to the killing, a year ago, of an Israeli antiwar demonstrator. An Israeli from Jerusalem was apprehended last week after an investigation that revealed a large local trade in stolen Israeli-Army weapons of the sort used in the incidents claimed by TNT. But investigators say the TNT attacks seem the work of other individuals.