Throughout the nearly 2000 years of history of the church, Christians have believed that Christ is truly man and truly God, and He is the Son of God, who is our Savior and our King. But that belief did not remain untested or tried. In fact most of the debates and controversies in the early Church were about the person of Christ – his deity and humanity, and the relationship of the two. The whole issue was how to understand how He was truly man and truly God at the same time in one person. It wasn’t until the mid-5th Century that a firm resolution was made but that didn’t mean that the heresies went away.
The doctrine about the person of Christ is still much relevant today, as we are still facing many unorthodox and heretical teachings about the person of Christ.