warghaha said:
Luke is not talking about God's mercy, though. He's talking about Jesus Christ, who shed his blood, as God, for the redemption of humanity (i.e., the church). Yet, because is merciful that he acted to atone for humanity's sin, and that was done through what action?
When I said, the atonement came from within ourselves, I was tryign to be philosophical.

God knews what is our intention, what we've done, etc. Based on that God will blessed us with His forgiveness. Not because of the sacrificial blood, etc.
Then from what you're saying, everything that God has revealed, starting way back in the OT with the Levitical law to the coming and fulfillment of the law in the person of Jesus was a ruse? Did God change his mind somewhere along the way? If so, where and when? And once again, if God knows our intention and work, do you not think he knows all about our feeble attempts at attaining righteousness? If so, then don't you think that God just might intervene on humanity's behalf in a much more merciful and loving way that to leave humans to their own devices to try and work out their atonement, forgiveness, and salvation by a means that is much more secure than their tainted works?
God is Self-Sufficient. He does not required something perfect as an atonement of sins.
Yet, humans are not perfect, and if they are going to receive God's forgiveness, then there is going to have to be sacrificial atonement for them before that forgiveness takes place. It is a requirement that is specifically stated in Scripture.
He create us as imperfect beings, so He already expect soemthing imperfect from us.
No, he did not create us imperfect. After Adam and Eve were created everything was declared "Very Good," not "Marginally Okay, with a taint of sin here and there." Instead, what took place is that Adam and Eve rebelled and then passed on their sin nature to everyone else subsequent to them, which is why if anyone now wishes to come into God's presence, there must be an atoning sacrifice performed in their behalf. And anything that is less than perfect will not appease the righteousness of God.
He know what is our limit. As long as we do the best, just remember, God is Most-Merciful, Most-Forgiving.
Again, our "best" is tainted with sin, meaning that it falls far short of God's standards of holiness and righteousness.
Isaiah 64:6 For all of us have become like one who is unclean, And all our righteous deeds are like a filthy garment; And all of us wither like a leaf, And our iniquities, like the wind, take us away.
Therefore, unless something much more substantial than "our best" represents us before God, to not only atone for our sins, but to offer forgiveness and redemption from them, then we will die our sins and receive the wages for them, which is death.
Romans 6:23
For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.