The major role of a prophet in the old covenant was as you stated. The new covenant prophet or prophetess does not add to the words that were already spoken by the ancient prophets but is inspired to understand their words and share them with the church. The gospels and the other writings of the New Testament very often refer to the ancient prophets; Matthew 1:22 , Romans 1:2 , Luke 24:44 , Matthew 2:15, 1 Corinthians 14:32 , 1 Corinthians 14:29,3 , Revelation 22:6 , Luke 1:70 , Acts 3:21 , 2 Peter 1:21 , 2 Peter 3:2 There are many more scriptures about this. Prophecy in the new covenant is not about revealing something new, but something old. Anyone who has learned by Yahwehs Holy Spirit must be in Jesus Christ else they will no nothing. John 6:45 The only reason any Christian understands the truth of Yahweh is in accordance with John 6:45 as Jesus is the mediator, our spiritual connection to Yahweh. We are taught by Yahweh, not men, in the same way as the ancient prophets, Jesus, the Apostles and all who are in Christ through all the time since then to today. Without the spirit of Yahweh the truth cannot be known. To receive the knowledge of the truth is by divine revelation , in other words prophecy. This is why Paul said to covet prophecy, 1 Corinthians 14:39 , and also 1 Thessalonians 5:20 . 1 Corinthians 14:3 , 1 John 2:27