George Shultz, not noted for bravery under fire as secretary of state, showed exceptional guts last week when he ignored the jackals on Capitol Hill and praised his precocious aide, Assistant Secretary Elliott Abrams -- thereby probably ensuring congressional approval of more contra`aid this year.

True, Shultz made a quick check with White House Chief of Staff Howard Baker before leaping to the defense of Abrams. But it was Shultz, not Baker, who saw instantly`that if the Reagan administration served up Abrams as sacrificial goat, the aidmfor-the-contras policy would be next. In reaching that same conclusion, Baker quietly sampled congressional opinion he respects, including Senate Republican leader Robert Dole.

The prospect of Abrams' being eased out appears distant. Barring new disclosures by heavy-hitter witnesses John Poindexter and Oliver North this summer, Abrams will probably stayn That should increase the chances of approval by the Democratic Congress of new contra aid. Why? Because Abrams' hard-line pro-contra credentials are insurance against right-wing backlash when the next -- and predictable -- U.S. diplomatic move comes in Nicaragua.

Abrams was alternately condescending and abrasive during the two days of testimony that got under the skin of some, and infuriated others, on the Senate and House Iran-contra investigating committees.

Abrams knows his claim of ignorance that the U.S. government was involved in the contra supply operation could be shredded in seconds by the future testimony of Marine Lt. Col. Oliver North. Likewise, he has not needed to be told that Poindexter's testimony, like North's, could pose serious legal questions about his veracity, in addition to sending him packing out of the administration.

That is why it took courage for the strong supporting arm of George Shultz to be extended to Abrams at the earliest possible moment -- at the end of the first of his two days of testimony. Shultz has to believe his assistant told Congress the truth last week.

Certainly that represents feelings at the heart of the State Department's elite Foreign Service corps. The cliquish Foreign Service clan often bitterly resents outsiders such as Abrams getting policy-making diplomatic posts in the State Department under the rank of deputy secretary. Ambassador Ronald Spiers, the senior Foreign Service officer in U.S. diplomacy, told us he telephoned Abrams after his testimony. ''I want you to know,'' he told Abrams, ''that you did a great job.''

The link between Abrams and aid for the contras is the same kind of link that, for example, ties the Strategic Defense Initiative to the president. Without Reagan, SDI would be doomed. Without Abrams, contra aid, for`all its stormy on-again, off-again perils in the congressional jungles, might well have lacked the driving energy to keep going.

''If they fired Abrams,'' a senior`administration official told us privately, ''the real sacrifice would not be Abrams but the fact that Reagan's Nicaragua policy would start down the slippery slope.'' Abrams' ouster would also undercut every`politician in Central America who has assisted the contra`policy, led by U.S. allies in Honduras.

A top-ranking Democrat on the Senate Foreign Relations Committee says privately that Abrams will ''probably'' fully restore his relations with Capitol Hill fairly quickly, if North and Poindexter support his testimony. Rep. Jim Slattery, a moderate Democrat from Kansas, who wants a political solution in Nicaragua, goes further. ''A lot of Democrats want to tack his hide on the wall, but I'm not making a judgment on the basis of the 6 o'clock news. Without Abrams, diplomacy will be more difficult.''

If Abrams now can show the same enthusiasm for promoting a political settlement that he has shown in promoting the contras, Reagan will get at least some of the $125 million he will ask in new contra funding later this year. That opinion, publicly stated to us by Jim Slattery, represents a conviction widely -- but very privately -- held by many on Capitol Hill.