My morning reading included Psalm 18 and verse 30 ministered to my soul greatly and made me think of psalm 19. Here are these two key texts on the authority (complete Divine authority), inerrancy (completely accurate and totally free from error), sufficiency (includes everything we need for life and godliness), perspicuity (it is clear and able to be understood), and infallible (dependable, unfailing) nature of the Bible.
This God—his way is perfect;
the word of the LORD proves true;
he is a shield for all those who take refuge in him.
(Psalm 18:30 ESV)
The law of the LORD is perfect,
reviving the soul;
the testimony of the LORD is sure,
making wise the simple;
the precepts of the LORD are right,
rejoicing the heart;
the commandment of the LORD is pure,
enlightening the eyes;
the fear of the LORD is clean,
the rules of the LORD are true,
and righteous altogether.
More to be desired are they than gold,
even much fine gold;
sweeter also than honey
and drippings of the honeycomb.
Moreover, by them is your servant warned;
in keeping them there is great reward.
(Psalm 19:7-11 ESV)