Christ expounded to them the scriptures of the Old Testament, which spoke of the Messiah, and showed them how they were fulfilled in Jesus of Nazareth, and now can tell them more concerning him than they could before tell him (v. 27): Beginning at Moses, the first inspired writer of the Old Testament, he went in order through all the prophets, and expounded to them the things concerning himself, showing that the sufferings he had now gone through were so far from defeating the prophecies of the scripture concerning him that they were the accomplishment of them. He began at Moses, who recorded the first promise, in which it was plainly foretold that the Messiah should have his heel bruised, but that by it the serpent’s head should be incurably broken.
First, There are things dispersed throughout all the scriptures concerning Christ, which it is of great advantage to have collected and put together. You cannot go far in any part of scripture but you meet with something that has reference to Christ, some prophecy, some promise, some prayer, some type or other; for he is the true treasure his in the field of the Old Testament. A golden thread of gospel grace runs through the whole web of the Old Testament. There is an eye of that white to be discerned in every place.
Secondly, The things concerning Christ need to be expounded. The eunuch, though a scholar, would not pretend to understand them, except some man should guide him (Acts 8:31); for they were delivered darkly, according to that dispensation: but now that the veil is taken away the New Testament expounds the Old.
Thirdly, Jesus Christ is himself the best expositor of scripture, particularly the scriptures concerning himself; and even after his resurrection it was in this way that he led people into the knowledge of the mystery concerning himself; not by advancing new notions independent upon the scripture, but by showing how the scripture was fulfilled, and turning them over to the study of it. Even the Apocalypse itself is but a second part of the Old-Testament prophecies, and has continually an eye to them. If men believe not Moses and the prophets, they are incurable.
Fourthly, In studying the scriptures, it is good to be methodical, and to take them in order; for the Old-Testament light shone gradually to the perfect day, and it is good to observe how at sundry times, and in divers manners (subsequent predictions improving and giving light to the preceding ones), God spoke to the fathers concerning his Son, by whom he has now spoken to us. Some begin their bible at the wrong end, who study the Revelation first; but Christ has here taught us to begin at Moses. Thus far the conference between them.
Here is the discovery which Christ at length made of himself to them. One would have given a great deal for a copy of the sermon Christ preached to them by the way, of that exposition of the bible which he gave them; but it is not thought fit that we should have it, we have the substance of it in other scriptures.