On this day in 1738 a man named John Wesley had a profound experience that changed his life – and arguably transformed the Church as well.

Wesley was an Anglican priest. He was a fervent preacher, but he was lacking in faith and growing in misery.

A spark of life began however when Wesley led a prisoner to Christ by preaching a gospel of faith and forgiveness, and he saw a man instantly transformed. His more enthusiastic Moravian friends encouraged him to have faith and to expect transformation and assurance.

On the morning of May 24, 1738, he opened his Bible to read the words: 'There are given unto us exceeding great and precious promises, even that ye should be partakers of the divine nature.'

That evening, a still depressed Wesley 'unwillingly' attended a Christian meeting in Aldersgate, London. There he heard a reading from the Reformer Martin Luther's Preface to the Epistle to Romans. At about 8.45 pm, as he heard Luther's words, something deep and dramatic took place.

In Wesley's words: 'While he was describing the change which God works in the heart through faith in Christ, I felt my heart strangely warmed. I felt I did trust in Christ, Christ alone for salvation; and an assurance was given me that He had taken away my sins, even mine, and saved me from the law of sin and death.'

Wesley went on with his brother Charles to pioneer the radical movement of Methodism, spreading evangelical revival across the country and the world. It probably would never have happened were it not for his 'Aldersgate experience'.

The strange warming of the heart has become emblematic for many interpreting their own spiritual experiences. It emphasises the importance of true conversion, the possibility of deep assurance and the power of an experiential salvation.

Since Methodism wouldn't be what it is without Aldersgate, today is celebrated across the Methodist Church.

A special liturgical prayer for the day reads:

'Almighty God, in a time of great need
you raised up your servants John and Charles Wesley,
and by your Spirit inspired them to kindle a flame of sacred love
which leaped and ran, an inextinguishable blaze.
Grant that all those whose hearts have been warmed at these altar fires,
being continually refreshed by your grace, may be so devoted
to the increase of scriptural holiness throughout the land
that in this our time of great need,
your will may fully and effectively be done on earth as it is in heaven;
through Jesus Christ our Lord. Amen.'