Benjamin Luther Sowell, 72, a retired Foreign Service officer and a founder of the First Spanish Baptist Church of Silver Spring, died of a heart ailment Friday at Holy Cross Hospital.

Mr. Sowell was born and reared in Buenos Aires, the son of Baptist missionaries. He received his secondary education in this country and graduated from the University of Richmond. He earned a master's degree in English from the University of Virginia in 1931.

In 1941, after teaching college in Richmond and working as a reporter in Buenos Aires, Mr. Sowell returned to the United States and joined the Foreign Service here.

He was a consul and labor attache at U.S. embassies in six Latin American countries and in Canada. After his retirement in 1966, Mr. Sowell served as a State Department escort to foreign diplomats touring this country.

He also devoted much of his time to helping Cuban refugees. About 1967, Mr. Sowell and a group of Spanish-speaking persons who had been active in the Baptist Church in their own countries, formed the original group that became the First Spanish Baptist Church of Silver Spring.

The church was originally formed as a mission of the Colesville Baptist Church, but became an independent church in late 1978. It is temporarily located at Clifton Park Baptist Church in Silver Spring. Its members are Spanish-speaking people, mainly from the Cuban community.

Mr. Sowell was the author of a book on the life of his father, a pioneer Baptist missionary in Argentina, and had compiled a directory of Washington's foreign language religious services.

Survivors include his wife, Ruby Lowry Sowell, of the home in Silver Spring; a son, J. Gregory, of Fredericksburg, Va.; three daughters, Virginia Brian, of Olympia, Wash., Anita Terry, of Wheaton, and Sydney Younger, of Baltimore; two brothers, Maurice, of Soddy, Tenn., and John, of Buenos Aires; a sister, Anne Margrett, of Memphis, Tenn., six grandchildren and two great-grandchildren.