Church is fun! It is more than eggs, hunting for chocolate, carols, music, parties, bunnies or a good-time. The church is people and relationships between people and God. The church exists because Jesus wanted it so, to give people life. The main player and driving force about the world-wide church is Jesus, the Messiah.
We can explain it another way, too.
Main Actor, Born - 3 AD, Death - 33 ad
Jesus Christ was murdered on a cross nearly two thousands years ago. On the third day after that crucifixion, He came out of the tomb He had been buried in. He was totally alive. Over the next 40 days Jesus appeared to His family, friends, and other people all over Israel. He ate with them, talked with them about what His resurrection meant for people. After all of these thousands of people witnessed Him ascending into heaven on that 40th day.
Christmas celebrates the birth of Jesus in a manger in Bethlehem, Israel. There are many festivals and celebrations besides Christmas that help us focus on Jesus and His work. Pentecost celebrates the Easter celebrates Jesus' resurrection from the tomb. Easter celebrates that death no longer has power over people, because Jesus is more powerful than death. Jesus gives victory over death to the people who follow Him and believe that He is the Son of God. Easter is the most important holiday for the follower of Jesus because Jesus broke the power of sin -- death. Death had ruled over mankind for centuries, but because of Jesus rising to life on the third day after He had died on the cross, He showed us His complete authority over everything. In fact, Jesus told everyone in the Gospel of John chapter 6.36 this amazing reality "Whoever believes in the Son has eternal life. Whoever rejects the Son will not see life. Instead, the wrath of God remains on him."
Pentecost is another festival, and is the first time in recorded history that the Holy Spirit of God came upon numerous people. This was the very beginning of the church. With Spirit empowering people, the purpose of the church became evident. To declare and celebrate Jesus and His authority over everything, especially death and sin. Pentecost, Christmas, Easter eggs, bunnies, games, family gatherings are all valuable to help remind of what Jesus has given to us. But the best thing that Jesus has done for humanity is to give us eternal life for all who believe in Him. This is something that the Holy Spirit directs into the heart of people. He does not force belief into people, but He prompts us to respond to His gentle calling to our heart, mind and soul. People who respond to the director's call, are called by Jesus to be born-again. Actually, re-born by the Spirit.