The challenge to Baptists committed to mission is, I suggest, finding a language that connects with people in a secular world, Kerrigan writes.
Before we can discover whether all Baptists must always be card-carrying evangelicals, we must first define what evangelical means.
David Bebbington's 1988 book, "Evangelicalism in Modern Britain: A History," offers four characteristics of evangelicals from their beginnings in the early 18th century to the 1980s.
A 2007 paper by Brian Harris explored Bebbington's work through the lens of postmodernism. I want to take Harris' thinking a step forward and examine its implications for Baptists.
For a long time, the hallmark of evangelical Christianity has been the understanding of the need to come to faith; that moment when repentance is expressed, faith is ignited and the gift of new life is received.
Harris supports Bebbington's historical analysis. From evangelicalism's hymnody through the evangelical missionary movement, conversion of the individual was the chief goal.
The earliest Baptist beliefs concerning the gathered church express these conversionist convictions.
In today's world, Harris references a more holistic understanding of salvation as embraced by 1974's Lausanne Covenant and 1989's Lausanne 2 Manila Manifesto.
He notes a greater openness to conversion as a journey toward the cross and "less certainty" in relation to the plight of the unconverted.
As a Baptist people, we stand firmly in this tradition of calling people to conversion.
My own Union's Declaration of Principle in its second paragraph states this: "That Christian Baptism is the immersion in water into the Name of the Father, the Son and the Holy Spirit, of those who have professed repentance toward God and faith in our Lord Jesus Christ."
The challenge to Baptists committed to mission is, I suggest, finding a language that connects with people in a secular world.
We must retain a conviction about conversion, but maybe one that emphasizes the rectification of our brokenness, rather than the avoidance of the penalty of sin, language largely seen as without meaning in the different moral world of the 21st century.
Bebbington's second characteristic of evangelicalism is activism.
Thomas Chalmers, a 19th-century Scot, was not an evangelical in his early life and commented that after the discharge of his duties "a minister may enjoy five days in the week of uninterrupted leisure." After his "conversion," Chalmers was reputed to have visited 11,000 homes in a single year.
The 19th century also saw the expansion of missionary and endeavor around the globe.
Shaftesbury and Wilberforce are among a host of men and women who sought social change as the outworking of the gospel. Such activism is prevalent to this day, but in the West it is often less evangelistic and more pastoral.
Again, this activism is captured in part of the Baptist Union of Great Britain (BUGB) Declaration of Principle, reminding us that, "It is the duty of every disciple to bear personal witness to the gospel of Jesus Christ and to take part in the evangelization of the world."
It is noteworthy that this activism is primarily seen as evangelistic engagement, something of a disconnect from the lived experience of most Christians.
In the words of John Wesley, "nothing ... is of greater consequence than the doctrine of the atonement."
But even to speak of the centrality of the cross demands a further refinement if evangelicalism is to be truly understood, for at its core has long been a commitment to the particular doctrine of substitutionary atonement.
While never universal, this doctrine has been normative within evangelicalism.
Harris affirms strongly the centrality of the cross but asks whether evangelicals need to broaden their understanding of it.
He argues "there is slowly a shift away from a focus on the cross as a substitutionary act of atonement to appease an offended deity, the cross as retributive justice, to an exploration of the cross as a vehicle of restorative justice. Rather than ask if the cross represents a victory over sin, death or the devil, it would seem appropriate for postmodern evangelicals to respond 'all of the above, and more beside.'"
When I consider today's Baptists with whom I am reasonably familiar - here in the United Kingdom, in Latin America outside of Brazil, in Canada and the northern states of the U.S. and the Caribbean - I would be tempted to characterize their convictions also as "all of the above and more."
Among Baptists in parts of sub-Saharan Africa, Brazil and the southern states of the U.S. where, arguably, the characteristics of a Christendom model still pervade, the cross is more often seen through the narrower focus of earlier years.
There was, early on, broad support among evangelicals that the Bible is inspired by God, though this was interpreted in various ways.
In the 18th century, Bebbington argues, the focus was less on a doctrine of Scripture per se as a desire that the Bible be seen as something to be trusted and commended for devotional use.
But from the 1820s onward "there began a body of evangelical opinion that began to focus on inerrancy, verbal inspiration and a literal interpretation of the Bible."
Brian Harris, writing in 2007, spoke of "a marked shift in the attitude of evangelicals towards the Bible."
Leaning heavily on Baptist theologian Stanley Grenz's approach at this point, someone he sees as representative of contemporary evangelicalism, Harris quotes Grenz as desiring to move away from seeing theology as using the Bible as a source for doctrinal propositions.
Rather, he argues for a theology conceived as the "reflection on the faith commitment of the faith community."
Grenz seeks to place as much emphasis on the role of the Holy Spirit in illuminating the text (with outcomes for discipleship) as in inspiring the text (with doctrinal outcomes).
Again, the first paragraph of the BUGB Declaration of Principle is pertinent here. "That our Lord and Savior Jesus Christ, God manifest in the flesh, is the sole and absolute authority in all matters pertaining to faith and practice, as revealed in the holy Scriptures, and that each church has liberty, under the guidance of the Holy Spirit, to interpret and administer his laws."
Here we find, not just that "the sole and absolute" authority is in the person of Jesus Christ to which the Scriptures bear witness, but the privilege and responsibility is given to the church, in community, to grapple with the meaning of the text for themselves under the guidance of the Holy Spirit.
The U.K. Evangelical Alliance Statement of Faith, to which many Baptists subscribe, seems at this point to be at odds with this Declaration of Principle. "The divine inspiration and supreme authority of the Old and New Testament Scriptures, which are the written Word of God - fully trustworthy for faith and conduct."
Some will argue that these statements are ultimately compatible. Ultimately, perhaps this is true. But in the here and now, asserting the Bible as the supreme authority can lend itself to a heavy-handed biblicism.
Acknowledging Jesus Christ, as revealed in the Scriptures, as the sole and absolute authority will still allow us to arrive at, and maintain, doctrinal convictions but also offers a more responsive framework with which to assess our mission engagement.
David Kerrigan is general director of BMS World Mission. A version of this article first appeared in Issue 2 2017 of Mission Catalyst, and is used with permission. This article is based on a much fuller paper delivered in April 2017 at the Hearts and Minds Theology Day at Regent's Park College, which you can read in full here.