What holy book do they use and what holy days do they observe?

What holy book do they use and what holy days do they observe?

(Jesus' message of love and brotherhood and his sacrifice for the human race. )
     In Christianity the holy book is the Holy Bible. Based on the teachings of Jesus, there are many holy days to go by in the Christian belief.
     The most important being Christmas, or the birth of Jesus Christ. This day falls on different day according to the branches, December 25 for Roman Catholics and Protestants and January 6 for Eastern Orthodox. Many Christians attend a midnight service in the church for celebration.
     Another important holy day is Easter, the day of the ressurection of Jesus, celebrated by a feast.
To prepare for the celebration of Lent begins 40 days before Easter, solely devoted to abstinence, penitence, and fasting.