What does it mean that Christ created the world? It means that he was incarnated into the world. Otherwise, what has God (who is a spirit) to do with the world (which is physical)? To physically create the world, God - the One Father of All - breathed into the world his Secret Fire, the Imperishable Flame, the One that belongs only with God. He did so to "let these things be" - so that his plans and intentions would become physical reality through his Word.
The form of that Flame is none other than Christ come into the world. Merry Christmas to you all - for on that day the universe was (ontologically, not temporally) created.
Jesus is like a baby elephant. A large elephant can be groped at by blind men and never be comprehended because of its large size. But if that elephant had a baby - something begotten to be of the same elephant nature yet small enough to be felt by the blind - then they could get a good idea of the large elephant.
There are no miracles at the highest level: If we could somehow understand God completely through one last final miracle, we'd find that there are no exceptions or surprises or inconsistencies in God, for God is perfectly logical and consistent in himself. All the lower level miracles would be contained and explained in the last miracle to give a complete picture of God.
The last, deepest, greatest miracle is the Incarnation. It is a miracle at the level of the nature of God himself. It reveals to us everything about God. "Anyone who has seen me has seen the Father". It is the miracle that explains all other miracles.
What is love? As it is written, "Greater love has no on than this: to lay down one's life for one's friends". So at the cross, Jesus displays the unconditional love that continued to love his sinful enemies even while we crucified him. He took on all our sins and their consequences, sacrificing himself and saving us.
Jesus Christ is God himself incarnated as a man. In God's act of true love for us, Christ came - God came as a man - to fulfill the plan for our salvation. For what power does anyone else have to stop the course of sin? To save us? To reach us, he humbled himself down to our level, and took on the human form that he first granted us. Like us, he was conceived, born, and raised, and became a man familiar with our sorrow, who experienced our pain. Despite being fully human, he remained morally perfect, so that he could serve as the perfect example for us. Moreover, this was necessary for the next key part of the plan: his crucifixion and resurrection.
I do not understand Jesus' death on the cross. There are theories of how it worked, but I doubt we have anything close to the full picture. This is only expected: the cross is nothing less than the intersection of all of existence - things on heaven and earth, visible and invisible, life and death, good and evil, sin and righteousness, God and his creation, story and Author - they all collide here. I think that a complete understanding of Christ's death and resurrection would require nothing short of the entirety of the mind of God. My telling of the story is utterly insufficient for it - nevertheless I will proceed.
The universe is actually designed by and for one person, and one person only: Jesus Christ, who is God himself. It's his game. He designed it to play it himself. Every parameter, every feature of the universe is designed solely for Christ's sake. Because Jesus made the universe to play it himself, it's an excellent, perfectly crafted game: it's made with incredible elegance, efficiency, and simplicity in its fundamental rules which are completely free of bugs or exceptions, yet the final result is rich and complex and intricate, and allows for a great deal of player expression.
How, then, shall we play? [...] Play like Jesus played: to express God's love back towards God, and to your fellow players. This is what the universe was designed for. After all, it was designed by and for Jesus.
This, at last, is the event for which all of creation was made and waiting for. God sent his son, in whom dwells the fullness of deity, to be incarnated as a human being. Thus began the final act in the grand story of the universe - the one that the whole universe had been building up to for 13.8 billion years.
The death and resurrection of Jesus Christ:
And here is the climax of the story: the singularity at the heart of existence, the purpose for which Christ came into the universe. Everything had been for this event. In the beginning, when God set the laws of the universe, he dictated that a hammer pounding a nail would be sufficient to drive it through Christ's body. When God created the Earth, he placed the iron atoms that would make up the spear that pierced Christ's side. When God created life, he designed it so that sufficient structural disruption would cause it, and therefore Christ, to die. When he created humans, he gave us sufficient brains for processing life, love, death, and resurrection. And when the serpent deceived Adam and Eve, God declared that the seed of the woman would crush the serpent. Everything - all the other events in the universe's history - had been building towards this moment. Through his death and resurrection, Christ makes us fully God's children. He completely reverses Adam's, Eve's, and all of our sins. He sets the course for all of creation - the whole universe - to be redeemed.