Catechumen

In ecclesiology, a catechumen (/ˌkætᵻˈkjuːmən, -mɛn/; via Latin catechumenus from Greek κατηχούμενος katēkhoumenos, "one being instructed", from κατά kata, "down" and ἦχος ēkhos, "sound") is a person receiving instruction from a catechist in the principles of the Christian religion with a view to baptism. The title and practice is most often used by Anglican,Lutheran,Methodist,Orthodox, Reformed/Presbyterian, and Roman Catholic Christians.Ecumenical organisations such as the North American Association for the Catechumenate are helping to, across several denominations, "shape ministries with adult seekers involving an extended time of faith formation and a meaningful experience of adult baptism at Easter."

Although catechumens existed by the time of the Letter to the Galatians (Strong's G2727), which mentions them, the practice slowly developed, from the development of doctrine and the need to test converts against the dangers of falling away. The Bible records (Acts 19) that the Apostle Paul while visiting some people who were described as "disciples", established they had received the baptism of John for the repentance of sins but had not yet heard of or received the Holy Spirit. Further, from the second century it appears that baptisms were held only at certain times of year, indicating that periods of instruction were the rule rather than the exception. The Catholic Encyclopedia notes: "As the acceptance of Christianity involved belief in a body of doctrine and the observance of the Divine law ("teach, make disciples, scholars of them"; "teaching them to observe all things whatever I have commanded you", Matthew 28:20 [see Great Commission]), it is clear that some sort of preliminary instruction must have been given to the converts." See also Council of Jerusalem. Justin Martyr, in his First Apology, cites instruction as occurring prior to baptism:

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