new moon: the first day of a lunar month, and the monthly holy day Israel kept on it
In Israel a month did not begin on a fixed date but on a sighting. Watchers looked for the first thin crescent after the moon had gone dark, and once their testimony was accepted the new month was declared. The day itself was a holy day, and it carried real weight:
- the law prescribed a fuller set of offerings for it than for any other monthly rite
- silver trumpets were sounded over those offerings at the sanctuary
- ordinary buying and selling slowed, and households gathered for a meal
Amos pictures merchants impatient for the day to be over so they can sell grain again, and 2 Kings treats it as one of the obvious days to go and see a prophet.
The word covers both the date and the observance. Greek speakers already used it for the plain first of the month, the day rent came due and new contracts began, and also for a monthly holy day of their own. Greek-speaking Jews took it over for the Hebrew term behind it (חֹדֶשׁ) wherever that word meant the opening day rather than the month as a stretch of time, and kept a separate word for the month itself (μήν).
Its single appearance in the New Testament, at Colossians 2:16, comes inside a set phrase: a festival, a new moon, or sabbaths. That trio, the yearly feast (ἑορτή), the monthly new moon, and the weekly rest day (σάββατον), runs all through the Greek Old Testament as shorthand for Israel's entire sacred calendar. Paul is not singling out three odd practices. He is naming the calendar whole, and then denying anyone the right to use it to pass judgment on the believers at Colossae.
Everything else on that calendar hung on this one day. A wrong sighting in the spring would put Passover on the wrong date, and a wrong sighting in the autumn would move the Day of Atonement. That is why the court guarded the declaration so carefully, and why the community at Qumran broke with the rest of Judaism over whether the moon should set the calendar at all.
What kind of religious setting the Colossian teachers were pressing new moon observance in.
- contestedA confident Diaspora synagogue was presenting itself as Israel's authentic wisdom tradition and pressing its calendar and purity rules on the believers, so the observance was ordinary Jewish covenantal life.; James D. G. Dunn, The Epistles to the Colossians and to Philemon, NIGTC (Grand Rapids: Eerdmans, 1996), 148-51, 173-79; James D. G. Dunn, "The Colossian Philosophy: A Confident Jewish Apologia," Biblica 76 (1995): 153-81; N. T. Wright, The Epistles of Paul to the Colossians and to Philemon, TNTC (Leicester: IVP, 1986), 101-02, 118-20
- contestedA Jewish core had been absorbed into a wider mixture of Hellenistic mysticism and local piety in which cosmic powers were held to govern the cycles of time and to require observance.; Eduard Lohse, Colossians and Philemon, Hermeneia (Philadelphia: Fortress, 1971), 115-17, 127-28; Peter T. O'Brien, Colossians, Philemon, WBC 44 (Waco: Word, 1982), 138-42; Douglas J. Moo, The Letters to the Colossians and to Philemon, Pillar New Testament Commentary (Grand Rapids: Eerdmans, 2008), 46-60, 219-25
- contestedThe days were kept as ritual defense against hostile spirit powers of magic and astrology, in the folk religion of the Lycus Valley.; Clinton E. Arnold, The Colossian Syncretism: The Interface between Christianity and Folk Belief at Colossae, WUNT 2/77 (Tübingen: Mohr Siebeck, 1995), 158-94, 214-19
- contestedJewish visionaries fasted on the festivals and new moons as ascetic preparation for heavenly ascent and for sharing in the worship of angels.; Ian K. Smith, Heavenly Perspective: A Study of the Apostle Paul's Response to a Jewish Mystical Movement at Colossae, LNTS 326 (London: T&T Clark, 2006), chs. 5, 8; Jerry L. Sumney, Colossians: A Commentary, NTL (Louisville: Westminster John Knox, 2008), 149-56; Scot McKnight, The Letter to the Colossians, NICNT (Grand Rapids: Eerdmans, 2018)
Whether Colossians 2:16 leaves new moon observance in place or retires it.
- majorityPaul forbids only the judging, not the keeping: his verb is "let no one judge you," not "do not observe," and he denies the Colossian teachers the right to condemn believers who do not keep the days, on the same pattern as Romans 14:5-6.; James D. G. Dunn, The Epistles to the Colossians and to Philemon, NIGTC (Grand Rapids: Eerdmans, 1996), 173-79; Douglas J. Moo, The Letters to the Colossians and to Philemon, Pillar New Testament Commentary (Grand Rapids: Eerdmans, 2008), 219-24; Markus Barth and Helmut Blanke, Colossians, Anchor Bible 34B (New York: Doubleday, 1994), 336-43; David W. Pao, Colossians and Philemon, ZECNT (Grand Rapids: Zondervan, 2012), 180-89
- minorityThe shadow and substance contrast of the next verse effectively retires the observances: they may still be kept, but they have lost their function now that Christ, the reality they anticipated, has come.; G. K. Beale, Colossians and Philemon, BECNT (Grand Rapids: Baker Academic, 2019), 224-27
- minorityPaul is defending the observance of the days against ascetic critics who wanted them fasted rather than feasted.; Samuele Bacchiocchi, From Sabbath to Sunday: A Historical Investigation of the Rise of Sunday Observance in Early Christianity (Rome: Pontifical Gregorian University Press, 1977); Ron du Preez, Judging the Sabbath: Discovering What Can't Be Found in Colossians 2:16 (Berrien Springs, MI: Andrews University Press, 2008)