65 The Apostle knew nothing else, and he determined to know nothing else: we men of feebler wit, and feebler faith, split up, divide and double Jesus Christ, constituting ourselves judges of the unknown, and blaspheming the hidden mystery. For us Christ crucified is one, Christ the wisdom of God another: Christ Who was buried different from Christ Who descended from Heaven: the Son of Man not at the same time also Son of God. We teach that which we do not understand: we seek to refute that which we cannot grasp.
We men improve upon the revelation of God: we are not content to say with the Apostle, Who shall lay anything to the charge of God's elect? It is God that justifies, who is he that condemns? It is Christ Jesus, that died, yea, rather, that was raised from the dead, Who is at the right hand of God, Who also makes intercession for us. Is He Who intercedes for us other than He Who is at the right hand of God? Is not He Who is at the right hand of God the very same Who rose again?
Is He Who rose again other than He Who died? He Who died than He Who condemns us? Lastly, is not He Who condemns us also God Who justifies us? Distinguish, if you can, Christ our accuser from God our defender, Christ Who died from Christ Who condemns, Christ sitting at the right hand of God and praying for us from Christ Who died. Whether, therefore, dead or buried, descended into Hades or ascended into Heaven, all is one and the same Christ: as the Apostle says, Now this 'He ascended' what is it, but that He also descended to the lower parts of the earth?
He that descended is the same also that ascended far above all heavens, that He may fill all things. How far then shall we push our babbling ignorance and blasphemy, professing to explain what is hidden in the mystery of God? He that descended is the same also that ascended. Can we longer doubt that the Man Christ Jesus rose from the dead, ascended above the heavens and is at the right hand of God? We cannot say His body descended into Hades, which lay in the grave.
If then He Who descended is one with Him, Who ascended; if His body did not go down into Hades, yet really arose from the dead, and ascended into heaven, what remains, except to believe in the secret mystery, which is hidden from the world and the rulers of this age, and to confess that, ascending or descending, He is but One, one Jesus Christ for us, Son of God and Son of Man, God the Word and Man in the flesh, Who suffered, died, was buried, rose again, was received into heaven, and sits at the right hand of God: Who possesses in His one single self, according to the Divine Plan and nature, in the form of God and in the form of a servant, the Human and Divine without separation or division.
Source: On the Trinity (New Advent)