Can you think of a celebration without food? Christmas cookies? Easter eggs? Halloween candy? 4th of July bar-b-que? Birthday cake? Wedding reception with all the great food? Good times are usually celebrated with good food. Jesus commemorated a special time with food, as well.
The night before he died, Jesus shared the Passover meal with his disciples which was a large meal with many rituals including a hide-and-seek game for the children and four glasses of wine for the adults. The centerpiece of the meal was a dinner, usually lamb in memory of the Israelites leaving Egypt. Right after the dinner part of the event, there was a third cup of wine presented known as the "Cup of Redemption." It was at this time that Jesus spoke these words of institution, when he said we should remember what he did with this food.
Matthew 26:26-28
26 While they were eating, Jesus took bread, and when he had given thanks, he broke it and gave it to his disciples, saying, “Take and eat; this is my body.”
27 Then he took a cup, and when he had given thanks, he gave it to them, saying, “Drink from it, all of you. 28 This is my blood of the covenant, which is poured out for many for the forgiveness of sins.
Different Christians have understood these words in different ways. Some have suggested that the bread and wine/juice are representative symbols of Jesus' body and blood. They would say that the bread helps us remember that Jesus gave his body and life for us. Others would say that since Jesus said, "This 'is' my body," that he really meant that it is his body. For a further look at this perspective, I would recommend reading through John 6, especially the verses that Jesus talks about being the bread of life. Lutherans take the "best of both worlds" approach by saying that physically the bread is still bread and the wine is still wine, but supernaturally (a way that is beyond [super] nature [natural]) Christ is giving us his very body and blood. Likewise, we eat the bread and drink the wine in natural ways, but receive his body and blood in a supernatural way, as a spiritual blessing. These days we call Baptism and Communion 'sacraments' or holy acts. The first Christians actually used the term 'mysterion' or mysteries, admitting the fact that how God does this is beyond human logic, yet we accept it on faith because that's what God's Word says.
Maybe this is a little odd. Maybe it is a hard selling point to those who are not Christians. Jesus did not go out of his way to make 'discipleship' easy - he knew that this is a big commitment, yet there is no other place to turn, for we know:
Acts 4:12
"Salvation is found in no one else, for there is no other name under heaven given to mankind by which we must be saved.”