The shock effect of Egyptian President Anwar Sadat's visit to Jerusalem, and his subsequent call for a preliminary conference in Cairo to prepare for Geneva, has caused great confusion in the Arab world.

The Arab states who have expressed their disapproval of the Sadat initiative cannot even agree as to the extent of their disapproval and the Libyan call for an anti Sadat summit in Tripoli is now being challenged by an Iraqi call for a rival and presumably more radical summit in Baghdad.

Jordan has chosen to remain on the fence by accepting to attend both the Tripoli and Cairo conferences, but only if all the other interested parties attend, which is tantamount to a declaration to stay home and join later if Arab unity is restored.

The great fear in the Arab world outside Egypt is that Sadat may have wrecked the unified stand that Egypt. Syria and Jordan had so carefully built with the backing of Saudi Arabia. The other Arabs fear that Sadat, in his desperate bid to reach a Middle East settlement so that he can put his own house in order, will sign a separate peace treaty with Israel, even though Sadat has made clear his attention not to do so.

Arab moderates fear that Syria may be pushed into a rejectionist stand and that the march to Geneva may be halted if Arab unity cannot be restored.

Nevertheless, there are a few straws in the wind that argue for what diplomats like to call cautious optimism. A careful analysis of King Hussein's speech last night indicates a swing toward the Egyptian position without approving unilateral action.

The king admitted that he had been taken by surprise by the Sadat initiative and sources close to the palace said he was personally affronted that Sadat had not taken him into his confidence. After all, in the previous weeks Hussein had been conducting his own shuttle diplomacy between Syria and Egypt trying to bring the two closer together. Sadat's surprise gambit was a humiliation for the king.

Hussein praised the boldness and courage of the Sadat initiative, however, and he stressed what may prove to be the most important factor - that the Sadat visit had broken the psychological barrier in Israel that resisted any change as useless because all Arabs wanted to push the Jews into the sea.

Thus, although Jordan could not oppose Syria completely, as the two countries have been building close ties for the last three years, the Hussein speech can be seen as more pro-Sadat that anti-Sadat.

The real message Hussein wanted to communicate was that since the deed had been done, it would be wrong to allow it to destroy Arab unity. "Should this ultimate split occur, God forbid, then the result would be catastrophic to the nation and to the entire Arab civilization," he said.

There is also an element of personal rivalry between Syria's President Hafez Assad and Sadat, but at his press conference in Damascus yesterday Assad did not say that Egypt and Syria were about to make a complete break and that "divorce" was too strong a word to describe the disagreement between the two countries.