The word Christian is a noun, not an adjective.
It appears three times in the bible and refers to
a person or persons. We err when we use the
word to describe something else (adjective); such as
a christian school, a christian family, or a christian life.
More correctly would be a school where Christians attend,
A family of Christians, or the life of a Christian. Christians
are disciples of Christ. A school is not a Christian.
The passages where Christian appears are:
Acts 11:26 The disciples were first called Christians at Antioch.
Acts 26:28. You will soon persuade me to become a Christian.
I Peter 4:16 suffer as a Christian.