It's interesting that this is the first question of this lesson. A few years ago the cover of TIME magazine caught my eye. It was shortly after Mel Gibson's movie, "The Passion Of The Christ" came out. The Cover Story was intitled "Why Did Jesus Have To Die?" The story was about an interdenominational mens bible study group who were sitting around discussing this fore-mentioned question. Finishing the article it saddened me that in the three pages the article took up that the question was not answered. The answer to that question and the question "How do we know John was refering to the Lamb Of God as a sacrifice is the same. God has always required a BLOOD sacrifice for the attonment of sin. As for the second part of the question, The only ones that were able to receive attonment were the Hebrew people. As it was to the Hebrews that the Laws were given and everyone else were gentiles, therefore, only the children of Abraham were considered worthy of forgiveness of their sins. So the thought of Jesus, The Lamb Of God, coming to take the sins of the WORLD would have been incomprehensible to a Jew.