10 I know indeed, that when these things are spoken, they will gnash their teeth upon us, with the devil who stirs them up, since they are troubled by the declaration of the true glory concerning the Redeemer. But the Lord, Who always has scoffed at the devil, does the same even now, saying, 'I am in the Father, and the Father in Me.' This is the Lord, Who is manifested in the Father, and in Whom also the Father is manifested; Who, being truly the Son of the Father, at last became incarnate for our sakes, that He might offer Himself to the Father in our stead, and redeem us through His oblation and sacrifice.
This is He Who once brought the people of old time out of Egypt; but Who afterwards redeemed all of us, or rather the whole race of men, from death, and brought them up from the grave. This is He Who in old time was sacrificed as a lamb, He being signified in the lamb; but Who afterwards was slain for us, for 'Christ our Passover is sacrificed.' This is He Who delivered us from the snare of the hunters, from the opponents of Christ, I say, and from the schismatics, and again rescued us His Church. And because we were then victims of deceit, He has now delivered us by His own self.
Source: Letters (New Advent)