The unsolved and confusing abduction of a Jordanian diplomat here was rekindled a deep and potentially explosive dispute between Jordan and Syria.

The conflict, in addition to renewing fears that the neighbors could end up at war, has underlined splits separating the Arab world and preventing it from working as a unit against Israel. As a result, some observers here are suggesting that, as is the case so often in inter-Arab rivalries, the kidnapping at dawn last Friday of Charge d'Affaires Hisham Moheisen has ended up benefitting the Jewish state more than anybody else.

The conflict between Amman and Damascus is not new. Jordan's de facto alliance with Syria's archenemy, Iraq, had eroded relations with the Damascus government last November to the point that until Saudi Arabia stepped in to mediate, entire divisions were facing each other on either side of the Jordan-Syria border.

Both sides stepped back from that brink of armed conflict. But now, despite spirited Syrian proclamations of innocence in the kidnaping, a war of words has resumed and Jordan has dismantled a joint immigration post at its border town of Ramtha and withdrawn its personnel from a similar arrangement in the Syrian town of Deraa.

In addition, Jordan's ambassador to Damascus has been recalled and his Syrian counterpart in Amman is reported to be preparing to follow suit.

Diplomatic relations, however, have not been severed. Nor have joint shipping and road transport companies been dissolved or Jordanian aircraft banned from Syrian sirspace.

In the insult-trading, Jordanian Prime Minister Modar Badran has accused Syrian special forces headed by Col. Rifaat Assad -- President Hafez Assad's brother -- of carrying out last week's kidnaping, in which three bodyguards were slain.

Various Syrian officials and official government radio and press statements have said Badran was a "barking dog," a particularly nasty insult in the Arab world, as well as a "spokesman for the Amercians and Israel," scarcely kinds words in the Middle East, either.

Although Al Baath, the newspaper of Syria's ruling Baath Party, said "Syria alone is capable, if it so chooses, to reduce Jordan to ashes," so far not troop movements have been confirmed along their border.

Another effect of the abduction has been to spotlight the level of insecurity in Beirut, for diplomats as well as others. The Jordanian prime minister told Jordanian officials that "if the Lebanese government is unable to protect the lives of diplomats, then we shall call on all missions to withdraw their embassies untio security and tranquility has returned."

Ever delighted to embarass Syria, Bashir Gemayel, head of the Israeli-backed Lebanese militias ruling the Christian heartland, suggested that all embassies move to his terrority and abandon mostly Moslem West Beirut, where they traditionally have been located.

Arab embassies and the entire diplomatic crops made separate representations to the embarrassed Lebanese government. Statistics published last month indicated that during 1980 along 16 embassies were attacked in one way or another. Half represented Arab states.

It Lebanon's reputation as a battleground for hostile Arab regimes thus remained unchallenged, the Moheisen case nonetheless so far lacks a clear-cut motive.

The most logical reason appeared to be the reported arrest early last week in a town near Amman of a Syrian sabotage team headed by a regular Army colonel. The team's reported mission was to kill the prime minister and attack Iraqi interests and members of the Moslem Brotherhood, an ultrareligious Islamic group deemed responsible for continued violence in Syria.

Anonymous callers, who in retrospect appear to have been frauds masquerading as pro-Syrian, early on said the diplomat would be executed unless Jordan broke off its dialogue with the Palestinians and returned seven Syrian pilots who had defected in recent months.

A monday afternoon deadline set by this now suspect caller came and went and no body has been found despite suggestions that the diplomat had been executed.