Paul starts this new passage off with the word "therefore." This means the upcoming thoughts are the result of his prior statements. In earlier verses, Paul explained that our relationship with God is through Christ, not through physical rituals such as circumcision. The salvation we have, through Christ, is complete and total. Not only does it remove the penalty of sin and restore our relationship to God, it also defeats the forces of evil which come against us (Colossians 2:13–15).
This verse uses those prior thoughts to refute a claim made by false teachers. These deceivers were telling Colossian Christians that they must follow specific rituals, rules, and regulations in order to be saved. In the next verse, Paul will call these concepts "a shadow of the things to come," or something much less important than Christ Himself. In contrast, Paul writes, "let no one pass judgment on you," with regard to four specific areas.
First, Paul notes dietary restrictions. The Mosaic law included many dietary aspects, such as not eating pork, an unclean food for Jews.
Second, Paul mentions holidays and feast days. Jewish laws included many specific celebrations such as Passover and the Day of Atonement, which were referred to as "festivals."
Third, a "new moon" refers to the new moon celebrations in the Mosaic law (Numbers 29:6).
Fourth, Paul mentions the Sabbath day. In Judaism, Saturday, the seventh day, was a holy day from sunset Friday till sunset Saturday, during which no work could be done (Exodus 20:8–11).
Paul clearly states, in this verse, that these kinds of rules are not requirements for saved believers. The passage immediately before this verse explained that Christ removed all sin and penalty through His sacrifice. As a result, there are no possible works we can do, or need to do, in order to be made righteous with God. This is an idea Paul gave additional detail to in Romans chapter 14.
Context Summary
Colossians 2:16–23 is an application of the ideas Paul mentions in the previous verses. Verses 6 through 15 explained the supremacy of Christ over deceptive, human-based thinking. In this passage, Paul explicitly states that rules, rituals, and self-denial are not the path of spiritual growth. Trying to grow, spiritually, through these efforts is as impossible as a body part developing naturally while severed from the head! Living under severe rules might look good to others, but it's not how God has called us to relate to Him as Christian believers.
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