1 Let us therefore fear, lest, a promise being left
  us of entering into his rest, any of you should seem
  to come short of it.
   2 For unto us was the gospel preached, as well as
  unto them: but the word preached did not profit them,
  not being mixed with faith in them that heard it.
   3 For we which have believed do enter into rest, as
  he said, As I have sworn in my wrath, if they shall
  enter into my rest: although the works were finished
  from the foundation of the world.
   4 For he spake in a certain place of the seventh day
  on this wise, And God did rest the seventh day from
  all his works.
   5 And in this place again, If they shall enter into
  my rest.
   6 Seeing therefore it remaineth that some must enter
  therein, and they to whom it was first preached
  entered not in because of unbelief:
   7 Again, he limiteth a certain day, saying in David,
  To day, after so long a time; as it is said, To day
  if ye will hear his voice, harden not your hearts.
   8 For if Jesus had given them rest, then would he
  not afterward have spoken of another day.
   9 There remaineth therefore a rest to the people of
  God.
  10 For he that is entered into his rest, he also hath
  ceased from his own works, as God did from his.
  11 Let us labour therefore to enter into that rest,
  lest any man fall after the same example of unbelief.
  12 For the word of God is quick, and powerful, and
  sharper than any twoedged sword, piercing even to the
  dividing asunder of soul and spirit, and of the
  joints and marrow, and is a discerner of the thoughts
  and intents of the heart.
  13 Neither is there any creature that is not manifest
  in his sight: but all things are naked and opened
  unto the eyes of him with whom we have to do.
  14 Seeing then that we have a great high priest, that
  is passed into the heavens, Jesus the Son of God, let
  us hold fast our profession.
  15 For we have not an high priest which cannot be
  touched with the feeling of our infirmities; but was
  in all points tempted like as we are, yet without
  sin.
  16 Let us therefore come boldly unto the throne of
  grace, that we may obtain mercy, and find grace to
  help in time of need.

...to Hebrews chapter 5