This is he who was spoken of through the prophet Isaiah: “A voice of one calling in the wilderness, ‘Prepare the way for the Lord, make straight paths for Him.’”
Matthew 3:3. The yoke of one crying in the wilderness Though this passage of the prophet Isaiah (40:3) ought not to be limited exclusively to John, yet he is one of the number of those to whom it certainly refers. After having spoken of the destruction of the city, and of the awful calamities that would befall the people, he promises a restoration that would follow.
We have here an account of the preaching and baptism of John, which were the dawning of the gospel-day. Observe, I. The time when he appeared. In those days (Mat 3:1), or, after those days, long after what was recorded in the foregoing chapter, which left the child Jesus in his infancy.
Commenting on Matthew 3:1-6
For this is he that was spoken of,.... These are not the words of the Baptist himself, as in Joh 1:23 but of the Evangelist, who cites and applies to John a passage in the Prophet Isaiah, Isa 40:3 and that very pertinently, since that "chapter" is a prophecy of the Messiah.