he Rev. John Randolph Taylor, a social activist pastor from Charlotte, N.C., who has spent much of the last 14 years working for reunion of southern and northern Presbyterians, was overwhelmingly elected moderator of the newly merged church today.

Taylor, 54, who began his ministry 27 years ago at the Church of the Pilgrims in Washington, D.C., was named on the first ballot to the highest elective post of the Presbyterian Church (U.S.A.), which was formed Friday.

The overwhelming choice of Taylor, who represents the smaller partner in the church merger, appears to reflect the determination of church leaders of both regions to bridge the Civil War-era rift that split the church 122 years ago.

Presbyterians meeting here today continued to ride the emotional high generated Friday by their formal vote to merge the 823,143-member Presbyterian Church in the United States, the southern branch, with the 2,351,119-member United Presbyterian Church in the U.S.A.

Starting Monday, however, the 988 commissioners, as church assembly delegates are called, will face a range of thorny issues, secular and religious.

To be considered are position papers on U.S. involvement in Central America, abortion, South Africa, the church's response to economic crises in cities hit by plant closings and problems engendered by transnational corporations.

Also ahead are several problems related to the merger, such as legal intricacies of joining separate pension plans and national staffs, and perhaps the touchiest: where to locate the reunited church's headquarters.

The southern church is established in Atlanta, while the northern is in New York at the Interchurch Center with several other Protestant denominations and the National Council of Churches.

Taylor, whose term as moderator lasts one year, expressed hope that the new church would "not get bogged down" over such arguments but would focus instead on its mission.

The merger, he said, "is a moment of opportunity for the spirit of God to take hold . . . . I hope we will consider not just how have we always done things, but ask instead, 'What is the best way to be the church in the 20th Century?' "

He outlined a program for the newly merged church that would combine evangelism and social action.

"I think Presbyterian reunion is not just talking about ecclesiastical merger," he told a news conference. "In the area where I live, what we are talking about is racial reconciliation."

At the same time, he continued, "We need very much to put equal emphasis on the proclamation of the gospel . . . . We need to be more purposeful in proclaiming the faith."

Presbyterians, the northern church in particular, have, like many mainline churches, been accused of overemphasizing social justice issues and slighting evangelism.

Taylor won 717 of 967 votes to defeat two opponents from the northern branch. His formal nominating speech was made by a black woman minister to symbolize his commitment to racial and sexual justice as well as church reunion.

During his seven-year pastorate of the 2,800-member Myers Park Presbyterian Church in Charlotte, he has established several social service agencies at the church and serves on various civic and community agencies working for racial and economic justice.

Under his leadership, Central Presbyterian Church in Atlanta, where he was pastor, was one of the first congregations of the southern church to elect women to its policy-making boards and to call a woman as associate pastor.

Born in China of missionary parents, Taylor was educated in Presbyterian schools in this country and at the University of Aberdeen in Scotland. He is married and has five daughters and a son.