He is widely known for his definition of evangelicalism, referred to as the Bebbington quadrilateral, which was first provided in his 1989 classic study Evangelicalism in Modern Britain: A History from the 1730s to the 1980s. Bebbington identifies four main qualities which are to be used in defining evangelical convictions and attitudes:

• biblicism, a particular regard for the Bible (e.g. all spiritual truth is to be found in its pages)
• crucicentrism, a focus on the atoning work of Christ on the cross
• conversionism, the belief that human beings need to be converted
• activism, the belief that the gospel needs to be expressed in effort

David Bebbington (along with Mark Noll and others) has exerted a large amount of effort in placing evangelicalism on the world map of religious history. Through their efforts they have made it quite difficult for scholars to ignore the influence of evangelicals in the world since the movement’s inception in the eighteenth century.

David Bebbington is married to Eileen, and has a daughter Anne and granddaughter Becky. He lives in the village of Bridge of Allan, and is a long time member of Stirling Baptist Church, where he has held various positions of leadership. He is also a regular lay preacher for churches affiliated to the Baptist Union of Scotland.

His books include Evangelicalism in Modern Britain: A History from the 1730s to the 1980s (1989), Victorian Nonconformity (1992), William Ewart Gladstone: Faith and Politics in Victorian Britain (1993), Holiness in Nineteenth-Century England (2000), The Mind of Gladstone: Religion. Homer and Politics (2004) and The Dominance of Evangelicalism: The Age of Spurgeon and Moody (2005).