I was listening to someone speaking about the relationship between Christ and the church. He said that Christ isn't king over the church: the church is His bride, not His subject. I didn't spit out my coffee when he said that, but I wanted to.
I understand where that idea comes from. Perhaps the most important distinction between believers on this side of the Cross and the Old Testament saints is union with Christ. David and Abraham were both justified freely by faith (Romans 4:1–10). But not a verse of Scripture even hints that either of them had died with Christ, was buried with Him, or was risen with Him. All of these things are true of us today (Colossians 3:1–5). Of course this is all individual.
There is something new that God has done now, corporately, compared to the Old Testament. There is the assembly, the Body of Christ (Ephesians 1:22–23), the habitation of God through the Spirit (Ephesians 2:19–22). Scripture tells us the assembly is not only the Body of Christ, but also the Bride of Christ (Ephesians 5:24–33). And it's entirely Scriptural to emphasize the intimacy of this relationship. Ephesians 5 does exactly that.
But there's a danger here: so many who want to emphasize the intimacy of the relationship between Christ and His bride, fall into the opposite error. The idea that "the church is His bride, not His subject" is just plain foolish. It doesn't have to be one or the other: it's both.
Scripture tells us quite plainly that the wife of the king isn't exempt from his authority. Yes, the assembly has a distinct and intimate relationship with Christ, but I can't find a single example in Scripture where the king's wife isn't one of his subjects.
Let's consider the case of David and Bathsheba (1 Kings 1:11-31). What does she call David? She calls him "my lord King David" (1 Kings 1:31). She calls him "my lord the king" (1 Kings 1:21, 27). She calls him "my lord" (1 Kings 1:17). Some people seem to have decided it's appropriate to use this last title for Christ, but not the others. Is there any reason the bride of Christ shouldn't address Him as "my Lord, the King?"
Let's consider the case of Esther. She refers to her husband as "the king" (Esther 5:1-4), and "O king" (Esther 7:1–4).
It seems to me like this is an example of folks allowing their theology to push them past what Scripture actually teaches. Both in Israel (David and Bathsheba) and in the nations (Ahasuerus and Esther), Scripture presents the queen as addressing the king as "king".
So we should be really careful about condemning someone for calling Christ the King. Let's not make someone a transgressor for a word, especially when the Scripture seems to support it.