Jerusalem — By using the threat of not withdrawing from the Sinai on April 25 for leverage, Israel has been testing Egypt. But it now seems highly doubtful that Israel will go through with that threat.
Israel's aims in the last-minute maneuver have been threefold:
* To elicit Egyptian compromise over outstanding Sinai border issues.
* To make a final try at influencing the Egyptians not to swerve radically away from Israel and the Camp David peace treaty once Sinai is fully in their hands.
* To refocus the attention of the Reagan administration -- increasingly, it is felt, diverted by the Falkland Islands crisis -- on what Israelis see as the unprecedented sacrifice they are making in giving up Sinai.
By late April 15, Israeli, Egyptian, and American officials had expressed optimism that differences between the two camp David partners would not delay withdrawal 10 days hence.
The possibility of not withdrawing from Sinai was hinted at this week by the Defense Minister Ariel Sharon and Foreign Minister Yitzhak Shamir. But Prime Minister Menachem Begin later pledged to fulfill international commitments, which is taken to mean pulling out by midnight April 25.
Mr. Sharon flew to Cairo April 15 to try to resolve problems concerning the border at the Arab town of Rafah in western Sinai and the Israeli resort of Taba along the Gulf of Aqaba. Statements from Egypt indicated it was would not cede any territory to Israel.
Mr. Sharon also was seeking assurances Egypt was not aiding the Palestine Liberation Organization (PLO) in Gaza or placing too many soldiers on the east side of the Suez Canal. These two points were believed to be minor, but the Israeli strategy appeared to set precedents for strict observence of the peace agreement.
To mediate last-minute problems, Walter Stoessel, deputy US secretary of state, was in Israel April 15 where he met with Mr. Begin.
The prime minister told Mr. Stoessel that Israel would carry out its treaty obligations and wanted Egypt to do likewise.
Despite the dispute with Egypt and the tension near Lebanon, technicians continued April 15 to dismantle Israeli buildings in the Sinai. But Mr. Sharon must move swiftly, now that Passover week has ended, to remove hundreds of Israelis illegally squatting in the Sinai city of Yamit.
Moreover, the West Bank and Gaza Strip, though less violent the past two days , remain explosive due to anger over the April 10 incident at the Dome of the Rock in Jerusalem, where an Israeli reservist shot and killed two Muslims.
Stone throwing continued in the West Bank and Gaza Strip, and Israeli soldiers again fired into crowds and forced open shops that were closed by a general strike. A sign of even tougher treatment of Palestinian demonstrators was a call by Israeli security officers for more flexible guidelines on firing into crowds.
An Israeli professor who specializes in Israeli-American relations told the Monitor he believes Mr. Begin cannot renege on the Sinai withdrawal without a loss of face.
Many diplomats in the Middle East continue to believe it is not a matter of if Israel invades, but when. But there are others who still see problems for Israel in any invasion.
A European diplomat in Tel Aviv told the Monitor he does not believe Israel, even now, is prepared for the costs of invasion.
''World opinion at the most would give them five days before the pressure became unbearable,'' he says. ''That may be enough time to move into Lebanon in a number of areas, but could they take control of Tyre (the Lebanese port city and Palestinian stronghold) in that time? I think not. If not, they simply hit Palestinians - but don't accomplish their apparent aim, which is to critically wound the PLO. And then they invite retaliation.''