President Carter and his wife, Rosalynn, spent yesterday afternoon on Maryland's Eastern Shore attending a special religious retreat at the farm of former Sen. and Mrs. Harold Hughes (D-Iowa).

Accepting an invitation that White House press secretary Jody Powell said was extended more than a year ago, the President and wife joined a small group of other guests for what was described as a "very private" gathering at the Hughes farm in Royal Oak.

The prayer meeting was held in private and attended by 15 other persons, including Sen. and Mrs. Lawton Chiles (D-Fla.), Sen. Pete Domenici (D-N.M.), Sen. Dewey Bartlett (R-Okla). Sen. Mark Hatfield (R-Ore.) and Mrs. San Nunn, wife of the Democratic senator from Georgia.

Carter flew to the Hughes farm, located at the mouth of the Choptank River on the Eastern Shore of the Chesapeake Bay, shortly after he returned from his regular Sunday school and worship services at the First Baptist Church here. He returned to the White House about five hours later.

When he served in the Senate, Hughes often sponsored prayer breakfasts for his lawmaker colleagues, and he has said his own religious faith helped him overcome a drinking problem. CAPTION:

Picture, Harold and Eva Hughes, left, walk with President and Mrs. Jimmy Carter at Hughes' farm near Royal Oak, Md., yesterday where Carters attended a special, very private religious retreat. The farm is on the Eastern shore. AP