It was the Puritans for whom assurance was a major theme. However it would be a mistake to think that it was the Puritans, or indeed the Reformers, who first thought of the Doctrine of Assurance. Beeke writes that some form of certainty or assurance has been taught throughout the Church’s history in various forms. Robert Letham writes that a lack of theological reflection on the issue of Assurance was due to a preoccupation of other issues such as Christology and Trinitarianism. In other words, assurance was not a foreign concept to the early church, it merely lacked any theological development. Beeke gives a number of reasons why assurance was not addressed with any theological precision in the early church:
1. An unbiblical underscoring of good works in relation to salvation, including an unwholesome attitude towards and desire for martyrdom; and a search for gnosis or knowledge which surpassed ordinary faith
2. Augustine never tackled adequately the area of assurance
3. There was no fertile soil for the doctrine of assurance in the Medieval Church. Certainty came through ecclesiastical and sacramental means rather than Christological and pneumatological means. Hence your assurance was based on whether you took the sacraments.