God took on the Karma of the whole world. In his earth-form He suffered the result of the wickedness of the past, present and future misdeeds of all these men that He had created. Through His suffering He removed the Karma that was due from these men. He made them perfect by knowing of His love.
In creating His beautiful world, He had also created sin. For every beautiful act, there is an equal ugly act. As men could do good and loving things, so also could they do the opposite. The loving and constructive acts nullify the destructive acts. From decay and decomposition come beautiful flowers and trees. Some say God created an imperfect world because of sin and its results, but God in his wisdom had that taken care of with his law of Karma. Eternity is the natural state of man. We are given the opportunity to live in this wonderful world full of beauty according to His plan, until we once again return to Eternity. He has ways to direct us to the knowledge of love for others. This is one part of his plan. God fulfilled his Karma as Christ and showed us how to make our own lives fulfilled too, and complete, no matter what suffering we encounter.
In one of our operational life times, we build our own future Karma with the things that we do before we commit to Eternity. On a personal level, we create our own world and we must live in it. By rectifying our past mistakes with new lives of love for others we fulfill our Karma. Christ shows us how to live a life of love in all that we do, no matter how hard our life may seem to us. We atone for what we have done in a previous life experience and everything is made right; although it might take more than one lifetime to complete.
Man builds his own future karma with the unloving things that he does before he commits himself to God. Between lifetimes, man returns to the spirit-world with God and his own spirit who knows everything in this state. Man knowingly chooses Karma in the next life that will exonerate him, and enable his soul to make a commitment to God and thereby gain Eternity (where he wants to be).
For man to work out his personal Karma, he needs to know of the Karma that God, in the person of Christ Jesus, worked out for mankind with His own personal suffering. Although sin was a part of the world God created; He suffered the Karma as Christ, thereby nullifying the sin.