Abelites

4th century

The Abelites were a small, fourth-century Christian sect in Hippo, North Africa which practiced sexual abstinence, although members were required to be married (this was because the Bible makes no mention of Abel having had any children). Each couple had to adopt two children, a boy and a girl, but in spite of this, they died out before the time of St. Augustine of Hippo.

References

Oxford Dictionary of the Christian Church, edited by F.L. Cross. (London: Oxford University Press, 1957)
Brewer, E. Cobham. Dictionary of Phrase and Fable. New and enlarged edition. (1894). Also available at: http://www.bibliomania.com/Reference/PhraseAndFable/data/3.html