Matthew 5:28

But I say unto you that every one looking on a woman in order to lust after her hath already committed adultery with her in his heart.

Matthew 12:35

The good man, out of the good treasure (heart) brings forth good things: and the wicked man out of the wicked treasure (heart) brings forth wicked things.

Matthew 15:19

For out of the heart proceed evil reasonings, murders, fornications, adulteries, thefts, false testimonies, blasphemies.

Treasury of Scripture Knowledge

Summary

And let none of you imagine evil in your hearts against his neighbour; and love no false oath: for all these are things that I hate, saith the LORD.

Bible References

Let

Matthew 5:28
But I say unto you that every one looking on a woman in order to lust after her hath already committed adultery with her in his heart.
Matthew 12:35
The good man, out of the good treasure (heart) brings forth good things: and the wicked man out of the wicked treasure (heart) brings forth wicked things.
Matthew 15:19
For out of the heart proceed evil reasonings, murders, fornications, adulteries, thefts, false testimonies, blasphemies.