Ultimately, that is the question which this web site attempts to answer,
so the first suggestion is to cruise through the site, picking articles to
read to help you answer the question. However, please consider an outline
of some of the evidence which strongly supports belief that the Bible is
the inspired word of God (which, by the way, the Bible claims in 2 Timothy
3:16)

1. Fulfilled prophecies. There are hundreds of predictive prophecies found
throughout the Bible, but especially in the Old Testament, in which a
Bible author accurately described specific events hundreds of years before
they happened. These prophecies are so specific, and are of events so far
into the future, that luck or coincidence simply cannot explain them away.
Just as an example, Old Testament scriptures predicted that the Messiah
would be born in Bethlehem (Micah 5:2), but be raised in Galilee (Isaiah
9:1). He would be born during the time of the Roman Empire (Daniel
2:36-45) and die for our sins in about 31 AD (Daniel 9:24,25). Old
Testament prophecies also predicted that the Messiah would be crucified
(Psalms 22:15-18) and that he would be betrayed for thirty pieces of
silver (Zechariah 11:10-13). No other book written by any author at any
time in human history has contained such specific and far-reaching
predictions. This would include the scriptures of other religions as well.
For further treatment of this subject, go the the reference section of the
web site. You will find articles on messianic prophecies in the section
“Jesus” and in the section “The Bible.”

2. The consistency of the Bible. The Bible, despite having at least forth
authors over the course of well over one thousand years is amazingly
consistent with itself in terms of its doctrinal teachings, its moral
teachings, its view of God and so forth. Many have claimed the opposite,
but a careful study of the Bible is consistent with the claim that the
Bible, as well as Jesus himself are “the same yesterday, today and forever
(Hebrews 13:8). There is an article exploring this idea more thoroughly
found in the references section under the heading “The Bible” entitled The
Ultimate Evidence.

3. The historical reliability of the Bible. The Bible is not a history
book, but it is loaded with historical references which can be checked by
comparison to what is know from other sources. Without exception, when the
Bible is compared to such sources, it proves to be an accurate account of
actual events. No other book of history, even those by the greatest
historians of the ancient world, can live up to this standard, showing
great evidence that the Bible is inspired. This question is dealt with
more thoroughly in an article under the heading “The Bible” entitled
“Historical and Archaeological Evidence Which Supports the Bible.”

4. The Bible works. If one will simply apply the principles found in the
Bible, they will work. The Bible is the best book on marriage, on
finances, on relationships, on government, psychology, and personal
ethics… the list could go on indefinitely. The curious person should
check out these claims for his or herself. In the words of Jesus, “If
anyone chooses to do God’s will, he will find out whether my teaching
comes from God or whether I speak on my own.” (John 7:17).

5. etc… There are many reasons to believe the Bible is inspired by God.
One could include the evidence of the miracles Jesus as well as many of
the Bible authors worked, some of which are a matter of historical record.
One could include the evidence for the resurrection of Jesus, which
clearly confirms his teachings. Perhaps the greatest evidence is found in
the lives of true disciples of Jesus who have been changed by following
the teachings of the Bible.