Through textual criticism and manuscript evidence: The biblical witnesses are older and more numerous than most classical works; thus, one can work with a high degree of textual fidelity.
Scholars such as Sir Frederic Kenyon point out that for many classical authors, there are centuries between the autograph and the oldest witness—whereas for the Bible, the dating and quantity of witnesses are significantly more favorable. The result: We can say with high certainty what was in the original text, and then examine the content.
Luke explicitly begins his Gospel with historical care (Lk 1:1–4 EÜ).
Scripture (EÜ): Lk 1:1–4.
Fathers/Teachers: Eusebius (Church History) as an early historical witness.