"I say this so that no one will deceive you with arguments that sound reasonable. For though I am absent from you in body, I am present with you in spirit, rejoicing to see your good discipline and the firmness of your faith in Christ. Therefore, as you have received Christ Jesus as Lord, so walk in him, rooted and built up in him and firm in your faith just as you were taught, overflowing with thankfulness. See to it that no one takes you captive through philosophy and empty deception according to the tradition of men and the rudiments of the world rather than Christ." (Colossians 2:4-8)
Paul's concern is that everything the Colossians see and do accord with Christ. That is, all thought, knowledge, wisdom, understanding, action, and all of life, inasmuch as it grows like a tree, should have Christ as its root. Inasmuch as it builds, it should have Christ as its foundation. With enslaving tradition in its conservative hand and deceitful philosophy in its radical hand, the "elemental spirits" of the world are the kings of the shadows. Christ is the reality, hidden but now revealed, exposing the shadows as exactly that.