Ephesians 4:5 what does "One faith" mean? Paul says that there is one faith.
I'm guessing that this mean theres only one faith that can save you. And that faith is in "believing" that Jesus died for your sins, and you're no longer a slave to death or sin.

Is my understanding wrong, or does it mean something different?
When Paul refers to “one faith,” I think he is referring to “the faith” (i.e. Christianity) spoken of elsewhere (emphasis added):


  1 Corinthians 16:13 NASB
  Be on the alert, stand firm in the faith, act like men, be strong.
  
  2 Corinthians 13:5 NASB
  Test yourselves to see if you are in the faith; examine yourselves! Or do you not recognize this about yourselves, that Jesus Christ is in you—unless indeed you fail the test?
  
  Galatians 1:23 NASB
  but only, they kept hearing, "He who once persecuted us is now preaching the faith which he once tried to destroy."
  
  1 Timothy 4:1 NASB
  But the Spirit explicitly says that in later times some will fall away from the faith, paying attention to deceitful spirits and doctrines of demons,
  
  Jude 1:3 NASB
  Beloved, while I was making every effort to write you about our common salvation, I felt the necessity to write to you appealing that you contend earnestly for the faith which was once for all handed down to the saints.


“The faith” refers primarily to “faith in Jesus,” which is trust/belief in Jesus as Lord, one and only son of God, creator, etc., and all that such belief entails. Paul (and others) implicitly assert that there is only one faith, and that we should all be united in it.


  Ephesians 4:13 NASB
  until we all attain to the unity of the faith, and of the knowledge of the Son of God, to a mature man, to the measure of the stature which belongs to the fullness of Christ.