Colossians is written against a specific teaching scholars call, for lack of a better name, the Colossian philosophy, known only from the letter's own warnings against it: a blend of ascetic practice, dietary rules, observance of festivals and new moons, and what the text calls "worship of angels," possibly a form of mystical practice claiming visionary access to the heavenly realm.
The letter's answer is to elevate Christ above every such intermediary, opening with a soaring hymn, 1:15 to 20, that calls Christ "the image of the invisible God" in whom "all things were created," a claim so complete that no additional angelic mediator or ascetic discipline could add anything to it. Because "in Christ dwells the fullness of deity, and you have been filled in him," the letter argues, cosmic speculation about angelic hierarchies and man made rules of asceticism are not deeper spirituality but a wrong turn, "a shadow of what was to come," now made unnecessary. Colossians also contains, at 3:18 to 4:1, a household code addressing wives, husbands, children, parents, and enslaved people, closely paralleled in Ephesians, a passage read very differently by different generations of interpreters navigating what in it reflects the specific first century household and what, if anything, is meant to bind believers permanently.