Concept:The declaration of God’s holiness as “Holy, holy, holy” appears in a prophetic vision of the Old Testament.
Explanation:The seraphim in heaven called to one another, saying, “Holy, holy, holy is the LORD of hosts.”
This event took place during the vision of the prophet Isaiah, recorded in the Bible at Isaiah 6:3.
Among the listed prophets, it was Isaiah who saw this vision and wrote down this declaration.
Therefore, the correct prophetic book and speaker associated with this statement is Isaiah.
Answer:C. Isaiah