Chambering means illicit or impure sexual intercourse, especially conduct understood as repeated or habitual rather than a single act.
The term occurs in the apostolic exhortation to live decently and not in chambering or wantonness. It represents conduct condemned as impurity.
The underlying Greek expression literally refers to beds and was used in Greek and the Septuagint for illicit intercourse. English versions since Tyndale rendered it “chambering” in this sense.