For the early Methodist societies, the doctrine of predestination was more than a mere intellectual debate. Predestinarian theology was instrumental in defining the respective identities of the societies. The ‘Free Grace’ controversy was therefore the ‘crucible of Methodism’; the furnace of debate that formed the Calvinistic Methodists and the Wesleyan Methodists, branded by their differing interpretations of predestination. The societies had strained relations with one another, exemplified by the ongoing debate between their respective heads, John Wesley and George Whitefield. The ‘Free Grace’ controversy proper ended in 1749, not when either side ‘won’ the argument over predestination, but rather when the doctrine of predestination ceased imparting its identity-giving characteristics. The decade-long dispute came to an end when George Whitefield resigned his post as head of the Calvinistic Methodist societies. The conclusion of this work offers suggestions for further avenues of inquiry which build upon the insights of the identity-giving functions of doctrine.