Questions about how persecuted Christians would have understood Psalms promising protection and rescue, whether it’s a contradiction for Jesus to say that some will be put to death but also that not a hair of your head will perish, and whether the Bible has been added to throughout the years.

How would Christians under persecution (such as those in Rome) have understood verses like Psalm 34:19–20 that promise protection and rescue by God for righteous people?

Is it a contradiction for Jesus to say both that some will be put to death and that not a hair of your head will perish (Luke 21:16–19)?

Is there evidence that would contradict my coworker’s claim that the Bible has been added to throughout the years?