The Promise Of The Transfiguration

Sunt quidam de hic stantibus qui non gustabunt mortem donec videant Filium hominis venientem in regno suo. Sermo itaque et promissio omnipotentis Dei, omni est repleta gaudio et consolatione in spe futurorum, eo quo sperare poterant omnes, qui prius promiserat universis de futuro; dum hic lici paucis, se firmat ostensurum, venientem in regno suo, antequam de proximo mortem gustarent. Et hoc quidem quia in ea claritate se tansformavit in monte coram discipulis, quos secum assumpsit, in qua venturum se promiserat in gloria Patris cum angelis suis. Et notandum quia regnum Christi, in quo venturus erat, ut eum viderent venientem in regno suo, ipse est gloria Patris; quia sicut regnum Christi, Patris est regnum: ita et gloria Patris Christi est gloria, quae ostenda est in monte, licet paucis, ut et ipsi qui viderant et caeteri qui audierant, illis repromissa se vidisse demum narrantibus, firmarentur ad fidem de filio hominis, quia visus est in gloria, quod ipse esset verus Filius Dei qui et filius hominis. Sanctus Paschasius Radbertus Corbeiensis, Expositio In Evangelium Matthaei, Liber VIII, Caput XVI Source: Migne PL 120.575a-b

There are some standing here who shall not taste death before they see the Son of Man coming in His kingdom. 1 This speech and promise of almighty God is full of all joy and comfort and hope for the future, because all are able to hope in what He promised for everyone in the future, while here it is given to a few whom He strengthens by showing them His coming in His kingdom before they taste death. And this is because He transfigured Himself in that brightness on the mount before His disciples who He took up with Him, in which He promised His coming in the glory of the Father and His angels. And it must be noted that the kingdom of Christ in which He shall come, so that they shall see Him coming in His kingdom, is the glory of the Father, because the kingdom of Christ is as the kingdom of the Father and thus the glory of the Father is the glory of the Son, which was shown on the mount to a few, so that they who saw and others who heard, who were told by those who saw what was promised, would be strengthened in faith concerning the Son of Man, because He was seen in His glory, that He is the Son of God who is the Son of Man. Saint Paschasius Radbertus, Commentary On The Gospel of Saint Matthew, Book 8, Chapter 16 1 Mt 16.28