And that from a child thou hast known the holy
scriptures, which are able to make thee wise unto
salvation through faith which is in Christ Jesus.
All scripture is given by inspiration of God, and is
profitable for doctrine, for reproof, for correction,
for instruction in righteousness: II Tim 3:15-16

We have also a more sure word of prophecy;
whereunto ye do well that ye take heed, as unto
a light that shineth in a dark place, until the day
dawn, and the day star arise in your hearts:
Knowing this first, that no prophecy of the scripture
is of any private interpretation.
For the prophecy came not in old time by the will
of man: but holy men of God spake as they were
moved by the Holy Ghost. II Peter 1:19-21

The scriptures itself testifies to it's inpiration.