2 Peter 1:20

Peter wanted to add a word of clarification about Old Testament predictions. "First of all" probably means that what Peter proceeded to say was of first importance. Bible students have recognized that what he said about Messianic prophecy in particular is true of prophecy generally. "Prophecy" is another word for the Word of God since it is what the Old Testament writers "spoke forth," the literal meaning of the Greek word propheteia, translated "prophecy." 2 Peter 1:21 helps explain what Peter meant by the last clause in 2 Peter 1:20.