Humans are interesting in that they understand the concept of good and evil. This dates back to the times of Adam and Eve, who according to the Bible commited the original sin. Before that point, they only knew goodness, as it was all that existed. However, when Satan tempted them to sin, he offered them "the knowledge of God", which is the ability to discern between good and evil. The only way they could have that knowledge was to sin by disobeying God, which is ironic because that was the only way evil could exist in the first place.
So when Adam and Eve ate from the tree of knowledge, two things happened: evil entered the world through their sin, and they recognized that evil with their newfound knowledge. Humanity was basically doomed from that point onward, as the very nature of sin and evil causes death and destruction and a conglomeration of...well...evil things. The only way to atone for sin at that point was to sacrifice things such as animals or crops and the like.
Jump forward a couple thousand years, and Jesus is born. He was a normal human child, except he was also the physical embodiment of God. He led a blameless life, and then was sacrificed on the cross. At that moment, he shouldered the evil in the world, taking it all upon himself. Then he came back to life three days later, after having payed the price for humanity's sin, which as I said before is death. In a way, he was the ultimate sacrifice, the final atonement for humanity's evil.
So what is the meaning of life, then? It is to recognize Jesus as our savior, as the one that payed the price for our sin, taking our place in death. If we acknowledge that he died for us, we show that we understand that his sacrifice allows us to live forever, since death is no longer a problem. Then we tell others about Jesus, because we want them to know that their sins are covered, that they do not need to fear death anymore. Finally, we follow the will of God, admitting that his knowledge is superior to our own for one simple reason: humanity failed in resisting sin (Adam and Eve), and God did not (Jesus). That and he made the universe, so he pretty much knows everything.
That's my take. Make of it what you will.