Paul warns the Colossians in Colossians 2:16 not to let anyone judge them 'in matters of food and drink or with regard to a festival, a new moon (νουμηνίας), or a Sabbath.' The term denotes the first day of the month in the lunar calendar, when the moon's crescent reappears after its dark phase. In Israel's cultic calendar, new moons were marked by special sacrifices and trumpet blasts (Numbers 10:10; 28:11-15). Some Jewish groups treated them as quasi-Sabbaths, restricting work or adding prayers. Paul's concern is that the Colossians are being pressured to observe Jewish calendrical regulations as if they were still binding under the new covenant. These practices were shadows pointing to Christ; now that the substance has come, the shadows lose their obligatory force.