Let it be known to you therefore, brethren, that through this man forgiveness of sins is proclaimed to you, and by him every one that believes is freed from everything from which you could not be freed by the law of Moses. Acts 13:38, 39, R.S.V.
Jesus didn't come bargaining with forgiveness; He came announcing it. Jesus didn't say, "I will forgive you if you will believe in Me." He said, "I am a forgiver--won't you please believe Me?" Jesus came to this earth to proclaim "good tidings of great joy, which shall be to all people" (Luke 2:0). The good news is not that I am forgiven, but that God is a forgiver!
The angels didn't say that the good news was only for the believers, but for all people. Unfortunately, not all of them would become believers in that good news. But the news remains constant, whether or not we believe it. In Christ, God announced forgiveness for all people. The lost will indeed be lost, not because God did not offer them forgiveness, but because they did not accept the Forgiver.
We cannot trust in that which is conditional if we must produce the conditions. Were God to say, "I will forgive you if you will believe in Me," we would begin to measure the quantity of our faith, then doubt we had produced enough.
By contrast, were God to say, "I am, by My very nature, a forgiver; I cannot be unforgiving, any more than I can be unloving," we would have something upon which to rest our confidence. Then, believing in Him, trusting in that unconditional forgiveness, we would be healed from further need to rebel.
When Jesus cried out from the still-prostrate cross, "Father, forgive them; for they know not what they do" (Luke 23:34), He was not begging for something the Father was unwilling to do. Rather, He was announcing for all to hear that the Father is a forgiver. And He hoped those cruel soldiers who were at the moment driving spikes into His wrists would hear that message, for someday they might come to know full well what they had done. And as they staggered under the awareness that they had driven nails through the Creator, He wanted them already to have heard the news "You are forgiven."
What could be more freeing from self-centered concerns than the assurance that our greatest need, freedom from the death penalty, has already been met at the cross of Christ?