While Christ has a Kingdom of Power over the whole world as He is divine, along with the Father and the Holy Spirit, is the Mediatorial Kingdom that has been delegated to Him as King only over the Church, or co-extensive with his Kingdom of Power over the whole world?

Before one comes down with an answer to the question, see what godly and learned men of old (who have studied the question more than us) have said on the topic.  As will be seen, most of the Westminster Divines, while acknowledging that Christ as Mediator has been given power over the whole world to govern all its affairs to his glory and the good of his Church, yet He is only Head and Mediatorial King over his Church, which He rules spiritually through his Word via his ministers and ordinances, to the detriment of those in the world who resist Him (Ps. 2:8-12).

The Westminster Divines on the Extent of Christ’s Mediatorial Kingdom