“You can’t go solo anymore,” warned Jim Singleton. Any individual or congregation wanting to join the Fellowship of Presbyterians (FOP) or A Covenant Order of Evangelical Presbyterians (ECO) needs to know that membership has its requirements.

A total of about 1,300 ministers and elders attended one or the other of back-to-back, two-day gatherings in late August in Colorado Springs and Atlanta to explore and, in some cases, join the fraternal twin organizations.

They heard major addresses by Richard Mouw, president of Fuller Theological Seminary, and Tim Keller, pastor of Redeemer Presbyterian Church (PCA) in New York City.

The major work, however, revolved around organizational development for those choosing to affiliate with FOP while retaining membership in the Presbyterian Church (U.S.A.), or join the ECO denomination after leaving the PC(USA).

The two major plenary speakers elevated two of the topics that comprise the “three-legged stool” that defines the twin organizations.

Mouw’s address lifted up the first leg: covenanted theology. “In the Presbyterian tradition we do claim loyalty to the confessions,” he said. That entails avoiding the two false paths, he said ― being people who “cross our fingers when we sign on the dotted line,” or being “grumpy conservatives who go off into a corner and say we alone are the faithful few.”

Instead, he made a case for orthodoxy based on what he called “a robust confessional integrity.” The unique status of Jesus as savior cannot be compromised, he said.

Specifically, Mouw compared the half dozen theories of the atonement to a set of golf clubs. Any one of the clubs may be the better choice at any one spot in the fairway, but it takes a putter the get ball into the hole. “Penal substitution is the putter,” he said, reminding that that is declared explicitly in the first question of the Heidelberg Catechism. “God did something for us that we could not have done for ourselves. If we lose that then we lose the heart of the Reformed faith.”

Then again, Mouw also addressed the major challenge of interfaith relationships, wherein claims of Christ’s uniqueness get interpreted as condemnations of all non-believers. Citing the Westminster Confession (XII,3), he reminded his listeners that infants dying in infancy “ ‘are regenerated and saved by Christ through the Spirit, who worketh when, and where, and how he pleaseth’ ” and that “the same applies” to others “ ‘who are incapable of being outwardly called by the ministry of the Word.’ ”

Keller highlighted a second leg, expounding on the missional challenge before the church. A pastor in the Presbyterian Church in America, a denomination formed by churches who left the former Presbyterian Church in the United States, (PCUS) prior to Presbyterian reunion in 1983, he was in unfamiliar territory, since most of his other worship co-leaders were evangelical women ministers (the PCA does not allow women to be ordained).

Keller made five points: that mission to be Christian aims to give witness to the Gospel; that it operates most powerfully as a grassroots, lay-led movement; that it is embodied in ways that bring racial reconciliation; that it is city-friendly; and that it is born out of suffering. Referencing the FOP/ECO initiative, he added, “There’s no way to start anything new without divisions, recriminations, on both sides.” But he said that if they remember the Gospel, letting it “give you that love and forgiveness toward anybody that’s mistreating you, mission will be born.”

The third leg was expounded by Singleton, the president of the FOP, by Dana Allin, the president of ECO, and by others. Member pastors and congregations of both organizations will be required to join in groups to share in mutual accountability.

Congregations in particular will be required to reflect, discuss and respond annually to 10 questions in the “Narrative on the Health of Mission and Ministry," which is adapted from a process used in the PCUS about 100 years ago. Further, they will need to meet three or four times a year with two or three other church sessions in their region to discuss and critique each churches’ progress in accomplishing them.

Ministers will meet in covenant groups, discussing and holding one another accountable to maintaining personal spiritual disciplines, personal conduct in ministry, and mutual encouragement and accountability.

The leaders announced the next event to be Jan. 30 – Feb. 1, 2013, in Orlando, Fla., and that it will include the first general synod meeting for ECO.