16 For we did not follow cleverly devised myths when we made known to you the power and coming of our Lord Jesus Christ, but we were eyewitnesses of his majesty.
17 For when he received honor and glory from God the Father, and the voice was borne to him by the Majestic Glory, "This is my beloved Son, with whom I am well pleased,"
18 we ourselves heard this very voice borne from heaven, for we were with him on the holy mountain.
19 And we have the prophetic word more fully confirmed, to which you will do well to pay attention as to a lamp shining in a dark place, until the day dawns and the morning star rises in your hearts,
20 knowing this first of all, that no prophecy of Scripture comes from someone's own interpretation.
21 For no prophecy was ever produced by the will of man, but men spoke from God as they were carried along by the Holy Spirit.
Peter, along with James and John, saw the Lord glorified, along with Moses and Elijah. In light of this it is crucial that we understand his statement "and we have the prophetic word more fully confirmed". Moses and Elijah are the representation of all the law and the prophets; Christ being the very embodiment and fulfillment of these.
In his first letter Peter begins with this:
1 Peter, an apostle of Jesus Christ, To those who are elect exiles of the Dispersion in Pontus, Galatia, Cappadocia, Asia, and Bithynia,
2 according to the foreknowledge of God the Father, in the sanctification of the Spirit, for obedience to Jesus Christ and for sprinkling with his blood: May grace and peace be multiplied to you.
3 Blessed be the God and Father of our Lord Jesus Christ! According to his great mercy, he has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead,
4 to an inheritance that is imperishable, undefiled, and unfading, kept in heaven for you,
5 who by God's power are being guarded through faith for a salvation ready to be revealed in the last time.
6 In this you rejoice, though now for a little while, if necessary, you have been grieved by various trials,
7 so that the tested genuineness of your faith—more precious than gold that perishes though it is tested by fire—may be found to result in praise and glory and honor at the revelation of Jesus Christ.
8 Though you have not seen him, you love him. Though you do not now see him, you believe in him and rejoice with joy that is inexpressible and filled with glory,
9 obtaining the outcome of your faith, the salvation of your souls.
10 Concerning this salvation, the prophets who prophesied about the grace that was to be yours searched and inquired carefully,
11 inquiring what person or time the Spirit of Christ in them was indicating when he predicted the sufferings of Christ and the subsequent glories.
12 It was revealed to them that they were serving not themselves but you, in the things that have now been announced to you through those who preached the good news to you by the Holy Spirit sent from heaven, things into which angels long to look.
13 Therefore, preparing your minds for action, and being sober-minded, set your hope fully on the grace that will be brought to you at the revelation of Jesus Christ.
14 As obedient children, do not be conformed to the passions of your former ignorance,
15 but as he who called you is holy, you also be holy in all your conduct,
16 since it is written, "You shall be holy, for I am holy."
17 And if you call on him as Father who judges impartially according to each one's deeds, conduct yourselves with fear throughout the time of your exile,
18 knowing that you were ransomed from the futile ways inherited from your forefathers, not with perishable things such as silver or gold,
19 but with the precious blood of Christ, like that of a lamb without blemish or spot.
20 He was foreknown before the foundation of the world but was made manifest in the last times for the sake of you
21 who through him are believers in God, who raised him from the dead and gave him glory, so that your faith and hope are in God.
22 Having purified your souls by your obedience to the truth for a sincere brotherly love, love one another earnestly from a pure heart,
23 since you have been born again, not of perishable seed but of imperishable, through the living and abiding word of God;
24 for "All flesh is like grass and all its glory like the flower of grass. The grass withers, and the flower falls,
25 but the word of the Lord remains forever." And this word is the good news that was preached to you.
The Lord, speaking to the jews, had this to say about Himself:
37 And the Father who sent me has himself borne witness about me. His voice you have never heard, his form you have never seen,
38 and you do not have his word abiding in you, for you do not believe the one whom he has sent.
39 You search the Scriptures because you think that in them you have eternal life; and it is they that bear witness about me,
40 yet you refuse to come to me that you may have life.
41 I do not receive glory from people.
42 But I know that you do not have the love of God within you.
43 I have come in my Father's name, and you do not receive me. If another comes in his own name, you will receive him.
44 How can you believe, when you receive glory from one another and do not seek the glory that comes from the only God?
45 Do not think that I will accuse you to the Father. There is one who accuses you: Moses, on whom you have set your hope.
46 For if you believed Moses, you would believe me; for he wrote of me.
47 But if you do not believe his writings, how will you believe my words?"
And to the travelers on the road to Emmaus:
25 And he said to them, "O foolish ones, and slow of heart to believe all that the prophets have spoken!
26 Was it not necessary that the Christ should suffer these things and enter into his glory?"
27 And beginning with Moses and all the Prophets, he interpreted to them in all the Scriptures the things concerning himself.
Later to the apostles:
44 Then he said to them, "These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled."
45 Then he opened their minds to understand the Scriptures,
46 and said to them, "Thus it is written, that the Christ should suffer and on the third day rise from the dead,
47 and that repentance and forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem.
48 YOU ARE WITNESSES OF THESE THINGS
49 And behold, I am sending the promise of my Father upon you. But stay in the city until you are clothed with power from on high."
All has been fulfilled by, through, and in Christ. The very moment that he gave up His Spirit the
new covenant of His blood took effect. He Himself prophesied this while still ”under the
28 After this, Jesus, knowing that all was now finished, said (to fulfill the Scripture), "I thirst."
29 A jar full of sour wine stood there, so they put a sponge full of the sour wine on a hyssop branch and held it to his mouth.
30 When Jesus had received the sour wine, he said, "It is finished," and he bowed his head and gave up his spirit.
11 But when Christ appeared as a high priest of the good things that have come, then through the greater and more perfect tent (not made with hands, that is, not of this creation)
12 he entered once for all into the holy places, not by means of the blood of goats and calves but by means of his own blood, thus securing an eternal redemption.
13 For if the blood of goats and bulls, and the sprinkling of defiled persons with the ashes of a heifer, sanctify for the purification of the flesh,
14 how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God.
15 Therefore he is the mediator of a new covenant, so that those who are called may receive the promised eternal inheritance, since a death has occurred that redeems them from the transgressions committed under the first covenant.
16 For where a will is involved, the death of the one who made it must be established.
17 For a will takes effect only at death, since it is not in force as long as the one who made it is alive.
And so the “transfiguration” on the mountain witnessed by Peter and the sons of Zebedee, in
conjunction with Jesus’ the death, resurrection, and ascension affirm the Word of God.
All “extra-biblical” revelation, (i.e. dreams, visions, new prophecy etc etc) is to be rejected.
They are an “adding-to” what has been completed. When God guides us by His indwelling
Spirit, or through our circumstances, or through others; it will line up (fully confirmed)
with what has been spoken and written by the apostles and prophets.