The community started originally following preaching efforts by John Thomas who expressed the idea that each individual should search the Bible for themselves, not follow church leaders or creeds. Hence the initial movement (which had yet to call itself Christadelphian) had some diversity as different members followed his teaching to varying degrees. This however soon proved unacceptable to the majority and it seems various statements of faith within the Christadelphian community emerged fairly early on in with various congregations forming their own.
Without any central form of church authority and a strong belief that baptism is ineffective without the correct beliefs the Christadelphians subsequently emerged as a highly creedal church. Whilst many independent congregations initially had their own statements of faith (some still do) this proved unsatisfactory to the majority. In order to ensure conformity of views a divisive process led to the adoption of inter-church statements as a basis for both fellowship and co-operation. The first statement used in this inter-congregational manner was the Birmingham Statement of Faith which was written in 1877. It can be found in the Ecclesial Guide written in 1883 by Robert Roberts who acted as a leader to the early Christadelphian movement after the founder, John Thomas died.
The development of Statements of Faith is closely tied to events in Christadelphian History. Today the most common is the Birmingham Amended Statement of Faith (or BASF) and it has had at least three additions. There was a Foundation Statement added in 1886, an Amended Clause was added in 1898, and a further clause was added to the Doctrines to be Rejected later when some Christadelphians became special constables (which many felt to be wrong). Close analysis shows a number of minor adjustments have also taken place.
It should be noted that in addition to the statemented doctrines there are many customary beliefs and practices which haven’t been defined within it such as the role of women, homosexuality, which practices are considered worldly, and certain prophetical beliefs and speculations.