When someone asks this question then use the acronym ICE by D. Huff. There are 3 important things to establish when affirming the reliability of an ancient document. First, is there internal evidence? Second, is there evidence that it is a changeless text? Third, is there external evidence that affirms the ancient document being evaluated? The acronym ICE develops a framework to answer these questions and establish that the Bible is a reliable text.

Internal Evidence

What does the Bible itself claim? Did the authors believe that they were writing an accurate account of the things taking place?

Turn in your Bible to Luke 1:1-4. Luke claims that he is writing an exact account that has been given by eyewitnesses and it has been investigated. In addition, the Bible does not seem to be a biased account, but instead it encompasses the embarrassing things of mankind in order to reveal the actual events. Too, internally the Bible claims that it is truth and there are over 5000 manuscripts of the New Testament that bear witness to its consistency.

One of the most famous critics of Christianity is Bart Erhman and even he says that Romans, 1 & 2 Corinthians, Galatians, 1 Thessalonians, Philippians and Philemon are undisputedly reliable texts (even though he does not believe them by faith).

Also, internal evidence is found throughout the claims of the Bible.

• Psalm 119:160 The sum of your word is truth, and every one of your righteous rules endures forever.
• John 17:17 Sanctify them in the truth; your word is truth.
• Ephesians 1:13-14 In him you also, when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it, to the praise of his glory.
• John 8:31-32 … So Jesus said to the Jews who had believed in him, “If you abide in my word, you are truly my disciples, and you will know the truth, and the truth will set you free.”
• John 17:8 For I have given them the words that you gave me, and they have received them and have come to know in truth that I came from you; and they have believed that you sent me. (Jesus speaking)

Another examination should include analyzing if the text has changed over time.

Changeless Text

Has it changed since it has been passed down? The Dead Sea Scrolls have been considered the greatest archaeological discovery. They were found in 1946 and eventually included findings in 11 caves. There were around 850 fragmented manuscripts that were uncovered. All of the texts were in some way related to the Bible and the only book of the Hebrew Bible that was missing was Esther. The Great Isaiah is a complete and noted manuscript that is dated back to 100-75 BC. Also books that were attested with copies included Psalms, Deuteronomy, Exodus, Genesis, and Leviticus.

External evidence that validates the accounts of the disciples and Paul.

Lastly, when examining ancient documents there must be other external evidence that validates the accounts. For example, Josephus was not a Christian, but was a Jewish historian writer of the Jews and Roman history. He mentions Jesus, John the Baptist and the death of James the brother of Jesus in his writings.