In 1668, the famous Puritan John Owen began publishing his magnum opus. Twenty-two years in the making, this first volume contained twenty-four “exercitations,” preliminary practices to help the reader understand what is coming in his magisterial study of the book of Hebrews. The tenth of these was titled, “Appearances of the Son of God Under the Old Testament.” It contains a precious discussion on Christ, especially as he appears as the Angel of the LORD, an actual person and character who appears time and again from Genesis to Malachi. This long-neglected treatise is a necessary back-bone holding up the perhaps longer-neglected and often misunderstood larger body of evidence demonstrating that the Second Person of the Trinity is literally present and known to the saints of the era prior to the incarnation. Anyone finding themselves desiring to learn more about this topic from one of the most respected of all the Puritans would do well to master the contents of this little book. We have also added dozens of quotations from Church Fathers and Reformers down to the present day showing the orthodoxy of the often denied doctrine that Christ was not merely typed and prophesied in the Old Testament, he was actually present in his person.