In an era when not just politicians, lawyers and Muslims but average men and women increasingly play fast and loose with truth, one may forgive a little scepticism when someone makes a claim.
“All scripture is breathed out by God”, Paul once wrote to Timothy.
That is a pretty significant assertion, and it is not one that can be substantiated by direct evidence. Christians cannot produce Polaroids of Paul or David in the process of writing the words of God surrounded by a nimbus or with an angel handing them a scroll. Nor can eyewitnesses confirm the presence of any Spirit Being overshadowing, indwelling, controlling or directing the authors of scripture. They are all long gone, if such witnesses ever existed.