66 So the Apostle moulding our ignorant and haphazard ideas into conformity with truth says of this mystery of the faith, For He was crucified through weakness but He lives through the power of God. Preaching the Son of Man and Son of God, Man through the Divine Plan, God through His eternal nature, he says, that He Who was crucified through weakness is He Who lives through the power of God. His weakness arises from the form of a servant, His nature remains because of the form of God. He took the form of a servant, though He was in form of God: therefore there can be no doubt as to the mystery according to which He both suffered and lived. There existed in Him both weakness to suffer, and power of God to give life: and hence He Who suffered and lived cannot be more than One, or other than Himself.
Source: On the Trinity (New Advent)