Evangelical is one of those words with quite a few different meanings. Its root is the New Testament Greek word for Gospel – evangel, meaning good news – so literally or etymologically an evangelical is a Gospel Christian. In one sense, then, all Christians are evangelical, since all believe in the Gospel, the good news of Jesus Christ. But etymology can only get you so far in understanding the meaning of words, and especially words that signify a particular group of people with a particular history. To get to the bottom of this, then, you have to look at what the word means in context and how it has been used.

Another meaning of evangelical is the one coined by Martin Luther in the Reformation. Luther would often use the term to refer to his church reform movement, and the Lutheran churches in Germany still bear the name today. This is closer to the meaning we're looking for. But evangelical in our sense originated not in 16^th century Germany but in 18^th century England and its American colonies – places where Calvin and not Luther was typically the Reformer of choice.

Evangelical in our sense traces its origins to the great religious revival of the 1730s, what is known as the Great Awakening in America, and more prosaically as the evangelical revival over here. At the centre of this were the preaching ministries of Massachusetts preacher Jonathan Edwards, Gloucester-born evangelist George Whitefield, and future founder of Methodism John Wesley.

What did they preach? They preached the Gospel – which in a Christendom context of cradle Christians was often a radical move. To people who had grown up thinking they were Christian but didn't necessarily attend church often or engage much on a personal level, they preached the fundamental importance of every individual experiencing for themselves a personal conversion to Jesus Christ through a deep and genuine repentance. This repentance was understood as a response to understanding the meaning and power of Christ's atoning work on the cross. Such a message found a ready audience in both colonial America and post-Restoration England, and many thousands came to hear these men speak and discovered for themselves through their words a lively new faith.

Evangelical historian David Bebbington has set out four marks that have over the past three centuries consistently distinguished evangelicalism from other Christian traditions, such as the High Church and Broad Church traditions. They are, first, its conversionism or commitment to converting people to Christ; second, its activism, especially in evangelism but also in social engagement; third, its crucicentrism, or focus on the cross and the atoning work of Christ as the central doctrine of Christianity; and fourth its Biblicism or commitment to the authority of the Bible and its central role in Christian preaching and piety.

So we find William Marsh in 1850 defining an 'evangelical believer' as 'a man who believes in the fall and its consequences, in the recovery and its fruits, in the personal application of the recovery by the power of the Spirit of God, and then the Christian will aim, desire, endeavour, by example, by exertion, by influence, and by prayer to promote the great salvation of which he himself is a happy partaker.'

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Referring to the Bible, John Wesley in the 18^th century said: 'Let me be a man of one book.' Famed evangelical Bishop of Liverpool J C Ryle declared in the late 19^th century that the first leading principle of evangelical religion is 'the absolute supremacy it assigns to Holy Scripture.'

Ryle's stress here on the supremacy of scripture was in part a response to the emergence of theological liberalism during the 19^th century, and especially from the 1860s as biblical criticism went mainstream in the English-speaking churches. Evangelicals resisted the liberal and critical movement on the whole, insisting instead on the divine inspiration and supreme authority of Holy Scripture, a characteristic that survives to this day.

The cross has always been at the centre of evangelical religion. In 1891, for example, leading Anglo-Catholic churchman Charles Gore began to argue that the Incarnation should be understood as the centre of Christian theology.

Methodists, however, were warned not to lose sight of the centrality of the cross: 'Give to the death of Christ its true place in your own experience and in your Christian work – as a witness to the real and profound evil of sin, as an overwhelming manifestation of Divine love, as the ground of acceptance with God, as a pattern of sacrifice to disturb us when life is too easy, to inspire and console us when life is hard, and as the only effectual appeal to the general heart of men, and, above all, as the Atonement for our sins.'

Conversion, likewise, has consistently sat at the core of what it means to be evangelical. Originally, in the 18^th century all evangelical preachers were expected to have undergone a conversion experience themselves so that they could speak with authority about what they knew. The conversion of early Methodist preacher Sampson Staniforth – then a solider on active service – evinces the basic ingredients of the conversion experience:

'As soon as I was alone, I kneeled down, and determined not to rise, but to continue crying and wrestling with God, till he had mercy on me. How long I was in that agony I cannot tell; but as I looked up to heaven I saw the clouds open exceeding bright, and I saw Jesus hanging on the cross. At the same moment these words were applied to my heart, 'Thy sins are forgiven thee'. My chains fell of; my heart was free. All guilt was gone, and my soul was filled with unutterable peace.'

Conversion did not necessarily start from a place of complete unbelief. People who already regarded themselves as Christian would often experience it, some of them already ordained! The essence of evangelical conversion was not necessarily new belief but a fresh insight into the reality of salvation and one's true standing before God. It was a stark recognition of one's sinfulness before God, and a personal acceptance of God's forgiveness, which had been bought through Christ's atoning sacrifice on the cross. This repentance was to be accompanied by a deliberate reorientation of life inspired by gratitude for Christ's sacrifice and the forgiveness it brings. John Wesley spoke of a person's 'sure confidence, that by the merits of Christ he was reconciled to the favour of God.'