Approximately 75% of the United States professes to be Christian. But many who profess to be Christian lead lives that call their profession into question. What are we to say about these individuals are they Christians or not? If believing in Christ is what it means to be a Christian, then what does that faith look like and how do we differentiate Christian faith from all other varieties? This booklet examines the concept of Christian faith from biblical, historical, and theological perspectives to seek to answer questions just like these.