Horatius Bonar emphasizes that the central theme of all prophecy is Jesus Christ, asserting that the Holy Spirit inspires prophets to testify about Him. He explains that the Bible, history, Psalms, and prophecies all point to Jesus, who is the answer to humanity's deepest needs. Bonar highlights Jesus' dual role as both the subject of prophecy and the one who fulfills it through His work as Prophet, Priest, and King. He calls for believers to search the Scriptures for Jesus and to bear witness to His glory, especially in a world that often overlooks Him. Ultimately, Bonar urges the Church to boldly proclaim the testimony of Jesus as the spirit of prophecy.