Simplify the following text for a Grade 9 native English-speaking person.
Original: Sola scriptura is sometimes called the formal principle of the Reformation , since it is the source and norm of the material principle , the gospel of Jesus Christ that is received sola fide ( `` through faith alone '' ) sola gratia ( by God 's favor or `` grace alone '' ) .
Simplified: The words `` Sola Scriptura '' , `` Solus Christus '' , `` Sola Gratia '' , `` Sola Fide '' and `` Soli Deo Gloria '' are not English words .