What then? The assembly must certainly meet, for they will hear that you have come. Therefore do what we tell you: We have four men who have taken a vow. Take them and be purified with them, and pay their expenses so that they may shave their heads, and that all may know that those things of which they were informed concerning you are nothing, but that you yourself also walk orderly and keep the law. But concerning the Gentiles who believe, we have written and decided that they should observe no such thing, except that they should keep themselves from things offered to idols, from blood, from things strangled, and from sexual immorality." Then Paul took the men, and the next day, having been purified with them, entered the temple to announce the expiration of the days of purification, at which time an offering should be made for each one of them. Acts 21:22-26
Paul had been accused of forbidding Jewish Christians to observe Jewish customs, which was not true. In the last two blog posts we warned about (a) elevating discretionary cultural customs to such a level of importance that they can become idols (which is a big mistake), and (b) of imposing the observance of such customs on others (also a big mistake). (Of course, many cultural traditions and holidays are inherently wrong, like Pride Month for example.)
In the five verses above, we need to consider the opposite: forbidding cultural traditions that are not inherently wrong. That is a big mistake as well.
I love celebrating Christmas (not a biblical holiday). I really do not care for Halloween (also not a biblical holiday). While many (most?) believers celebrate one or both of these holidays, there are some well-meaning Christians who crusade against Christians observing them. Granted, if a person makes either holiday an idol, or if his celebration includes clearly unbiblical practices, he is in error. If he tries to insist others observe those holidays, he is again in error.
But so is the one who condemns others for what is not inherently wrong—or any of his business!
What has this to do with the text? Paul was not banning Jewish customs that were not sinful. To prove it, he received and followed some advice about joining some Jewish men in a particular tradition (probably a Nazarite vow).
BTW: I pray no one misses the point, thinking this post is about Christmas and Halloween!