“And this voice which came from heaven we heard, when we were with him in the holy mount.”
King James Version (KJV)
1:18 And we - Peter, James, and John. St. John was still alive. Being with him in the holy mount - Made so by that glorious manifestation, as mount Horeb was of old, #Exod 3:4|,5.
2Pe 1:18 And this voice . . . we heard. Peter and James and John, his companions on "the holy mount" (Mt 17:1-6). James was now dead (Ac 12:2), but John was still alive.