Him we proclaim, warning everyone and teaching everyone with all wisdom, that we may present everyone mature in Christ. (Col 1:28 ESV)

We proclaim a person not a system so we may present everyone mature in Christ.  It is not a system of thought that we rely on but a person, Christ.  That is not to say theology is unimportant.  To speak of Christ is to declare a theology of Christ.  To say we believe in Christ is to make certain theological claims about Christ - who he is, the nature of his essence; what he did on our behalf, the nature of his death and resurrection.  Our thinking about Christ must be informed by Scripture (all wisdom).  Paul did not discuss Christ in a discussion ideas, he proclaimed him.  He proclaimed the work of Christ on the cross on our behalf on the cross, the present work Christ does for us by His Spirit, and what Christ promises to do for us in the future.