I will leave you to argue against the others who are hawking the 'substitutionary atonement' theory of Christ's work of salvation.
I would like to point out to you, though, that those of us who follow Christ in what is arguably the living continuation of the original Church (commonly called the Orthodox Church now) find the theory of God providing Himself a blood sacrifice barbarous. Our hymnogaphy speaks of Christ "trampling down death by death," and sees the fundamentals of our salvation in the uniting of human nature to the Divine nature in the person of Christ.
The theory the others present ignorantly as standard Christian doctrine is actually a rather late and provincial development, being first proposed by Anselm of Canterbury after the Latin church had already fallen into heresy and schism. It is quite unknown in the Christian East (whether among Orthodox, Monophysite or Nestorian), and not universally accepted in the West, though one can find exponents of it in most Western confessions.
I don't know about the big words, but THIS works for me:
NIV 1 Timothy 1:13
Even though I was once a blasphemer and a persecutor and a violent man, I was shown mercy because I acted in ignorance and unbelief.
NIV Romans 9:15-16
15. For he says to Moses, "I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion."
16. It does not, therefore, depend on man's desire or effort, but on God's mercy.
4. But when the kindness and love of God our Savior appeared,
5. he saved us, not because of righteous things we had done, but because of his mercy. He saved us through the washing of rebirth and renewal by the Holy Spirit,
6. whom he poured out on us generously through Jesus Christ our Savior,
7. so that, having been justified by his grace, we might become heirs having the hope of eternal life.
NIV James 2:12-13
12. Speak and act as those who are going to be judged by the law that gives freedom,
13. because judgment without mercy will be shown to anyone who has not been merciful. Mercy triumphs over judgment!