I Catherine, servant and slave of the servants of Jesus Christ, write to you in His precious Blood: with desire to see you a lover and follower of truth and a despiser of falsehood. But this truth cannot be possessed or loved if it is not known. Who is Truth? God is the Highest and Eternal Truth. In whom shall we know Him? In Christ sweet Jesus, for He shows us with His Blood the truth of the Eternal Father.
His truth toward us is this, that He created us in His image and likeness to give us life eternal, that we might share and enjoy His Good. But through man's sin this truth was not fulfilled in him, and therefore God gave us the Word His Son, and imposed this obedience on Him, that He should restore man to grace through much endurance, purging the sin of man in His own Person, and manifesting His truth in His Blood.
So man knows, by the unsearchable love which he finds shown to him through the Blood of Christ crucified, that God nor seeks nor wills aught but our sanctification.
There is here, I think, a point not always appreciated.
It's common to react to the idea that Jesus' death was "necessary" with the objection that it seems monstrous for the Father to require His Son to die in agony. What's overlooked is that His Son's agonizing death is a reflection of the Father's own unsearchable love for us and desire for our sanctification.