When the average American goes to church, they'll most likely see an American flag and the Christian flag displayed somewhere in the pulpit. Many people know the story behind the American flag, but there aren't too many that know the origins of Christ's flag.
Ironically, in order to understand the design of the Christian flag, you need to know a little about the American flag. The American flag's design had a lot to do with the design of the Christian flag. The Christian flag has its origins in Brighton Chapel on Coney Island. On a September day in 1897 the superintendent of the church's Sunday School, Charles C. Overton, was forced to give an impromptu lecture to his students because the scheduled speaker didn't show up to the event. Overton didn't know what he was going to talk about until he saw the American flag outside of the chapel. He was inspired by the flag's symbolism and importance, so he gave a speech asking the students what a flag representing Christianity would look like. Overton thought about his speech for years, and in 1897 he got together with Ralph Diffendorfer, the secretary of the Methodist Young People's Missionary Movement, and designed and promoted the flag.
The main features of the flag are the white background, the blue square, and the of course the cross. The flag's most notable feature is the Christian cross, the symbol the majority of Christians in the world view as a symbol of their religion. The red color of the cross represents the blood Christ shed for their sins. The cross and blood have been used since the beginnings of Christianity to symbolize salvation through Jesus.
The white that makes up the majority of the flag depicts the symbolic nature of white in the Bible, where white clothes are equated with purity and forgiveness. When the Bible mentions people who have been cleansed of their sins, their souls are usually described as being white as snow. The white also symbolizes another important theme in the religion: surrender. According to vexillology (the study of the symbolic meaning of flags), a white flag is usually used as a symbol of surrender, a reference to the Biblical description Jesus' non-violence and surrender to God's will. The blue square represents faithfulness, truth, and sincerity. The blue also stands for the sacrament of baptism, where Christians use water to ritually cleanse themselves of their sins and being life anew as a follower of Christ.
Today, the Christian flag is used by millions of Christians around the world and is a popular way for people to show pride for their religious beliefs.