Julia is among the people addressed by name in a portion of the book of Romans in which Paul the Evangelist sends personal greetings. In this portion of greetings, Julia is coupled with Philologus and so some scholars have speculated that she might be the wife or sister to Philologus. The fact that she is being greeted by name indicates that she was a Christian.
Julia is mentioned by name in Romans 16:15.
Next person in the Bible: Julius