No compulsion is there in religion.
Rectitude has become clear from error.
So whosoever disbelieves in idols
and believes in God, has laid hold of
the most firm handle, unbreaking; God is
  All-hearing, All-knowing.

God is the Light of the heavens and the, earth;
the likeness of His Light is as a niche
  wherein is a lamp
  (the lamp in a glass,
the glass as it were a glittering star)
  kindled from a Blessed Tree,
an olive that is neither of the East nor of the West
whose oil wellnigh would shine, even if no fire touched it;
  Light upon Light;
  (God guides to His Light whom he will.)
  (And God strikes similitudes for men,
  and God has knowledge of everything.)
in temples God has allowed to be raised up,
and His Name to be commemorated therein;
therein glorifying Him, in the mornings and the evenings,
are men whom neither commerce nor trafficking
  diverts from the remembrance of God
and to perform the prayer, and to pay the alms,
fearing a day when hearts and eyes shall be turned about,
that God may recompense them for their fairest works
  and give them increase of His bounty;
and God provides whomsoever He will, without reckoning.

  And as for the unbelievers,
their works are as a mirage in a spacious plain
  which the man athirst supposes to be water,
till, when he comes to it, he finds it is nothing;
  there indeed he finds God,
and He pays him his account in full; (and God is swift
  at the reckoning.)
or they are as shadows upon a sea obscure
  covered by a billow
  above which is a billow
  above which are clouds
shadows piled one upon another;

God knows the Unseen in the heavens and the earth;
He knows the thoughts within the breasts.
It is He who appointed you viceroys in the earth.
So whosoever disbelieves, his unbelief shall be
charged against him; their unbelief increases
the disbelievers only in hate in God's sight;
their unbelief increases the disbelievers only
  in loss. (35:38-39)

God is He that looses the winds, that stirs up clouds,
and He spreads them in heaven how he will, and shatters them;
then thou seest the rain issuing out of the midst of them,
and when He smites with it whomsoever of His servants
  He will, lo, they rejoice,
although before it was sent down on them before that
  they had been in despair.

So behold the marks of God's mercy,
how He quickens the earth after it
was dead; surely He is the quickener
of the dead, and He is powerful
  over everything.
But if We loose a [hot] wind, and they see [the earth]
  growing yellow,
  they remain after that unbelievers.

Thou shalt not make the dead to hear,
neither shalt thou make the deaf to hear the call
  when they turn about, retreating.
Thou shalt not guide the blind out of their error
  neither shalt thou make any to hear
except for such as believe in Our signs, and so surrender.

God is He that created you of weakness, then He appointed
after weakness strength, then after strength He appointed

  That then is God your Lord;
  there is no god but He,
  the Creator of everything.
  So serve Him,
  for He is Guardian over everything.
The eyes attain Him not, but He attains the eyes;
  He is the All-subtle, the All-aware. (6:102-103)