We were not eyewitnesses to the coming of the Lord Jesus Christ but there were eyewitnesses like Peter who beheld his majesty. They heard the Father speak to the Son from heaven. Let me repeat that…they heard God say, “This is my Son with whom I am well pleased.” It seems that one could not get anything better than that.
However, even though we were not eyewitnesses we have something more sure—the written Word of God. Not only are God’s utterances from heaven recorded but we are told what they mean. The details of which the apostles didn’t probably know were given to them by God the Holy Spirit.
2 Peter 1:21
[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.
The image is that of wind being blown into a sail to carry along a ship. The Holy Spirit (Wind) carried along those eyewitnesses to write the prophetic word and it is more sure!
2 Peter 1:19
[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
We think that eyewitness accounts can’t get any better or we might even think since I wasn’t there then I’m lacking information and therefore cannot believe. Well the eyewitnesses have given us the Word that is more fully confirmed. It is the trustworthy source by which to know God! Be thankful for the Word and pay close attention to it.