Are your thoughts holy?
Pr 23:7 For as he thinketh in his heart, so is he: Eat and drink, saith he to thee; but his heart is not with thee.
Your thoughts are as loud to God as your words are when you speak loudly.
Pr 15:26 The thoughts of the wicked are an abomination to the Lord: but the words of the pure are pleasant words.
Dan 5:24 Then was part of the hand sent from Him; and this writing was written.
:25 And this is the writing that was written, ME'-NE, ME'-NE, TE'KEL, U-Phar'-SIN.
:26 This is the interpretation of the thing; ME'-NE; God hath numbered thy kingdom, and finished it.
:27 TE'KEL; Thou art weighed in the balances, and art found wanting.
:28 PE'RES; Thy kingdom is divided and given to the Medes and Persians.
How would you like the hand of God to write your thoughts across the sky for everyone to see? He could.
Jn 8:6 This they said, tempting Him, that they might have to accuse Him. But Jesus stooped down, and with His finger wrote on the ground, as though He heard them not.
Jn 8:8 And again He stooped down, and wrote on the ground.
We must not only repent of sin of our words and actions, but of sinful thoughts also.
Is 55:7 Let the wicked forsake his way, and the unrighteous man his thoughts: and let him return unto the Lord, and He will have mercy upon him; and to our God, for He will abundantly pardon.
Ps 19:14 Let the words of my mouth, and the meditation of my heart, be acceptable in Thy sight, O Lord, my strength, and my redeemer.
Ps 51:6 Behold, thou desirest truth in the inward parts: and in the hidden part Thou shalt make me to know wisdom.
Sin of the body first begins in the thoughts and heart.
Mt 5:28 But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
Satan will come to you in thoughts to tempt you to sin.
James 4:7 Submit yourselves therefore to God. Resist the devil, and he will flee from you.
Don't argue with the devil. That is not resisting. It is what he wants. Once you get into a conversation with the devil, he has the battle half won.
Phil 4:8 Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things.
Rom 12:21 Be not overcome of evil, but overcome evil with good.
How do we know when evil thoughts come from our heart or from the devil?
If our immediate reaction is hatred of the thought it is from the devil. Otherwise it came from us if we try to justify or explain it.
If we are continually bombarded in one area of our christian life by attacks from the devil, we know he has been listening to our words or watching our actions. He can't read our minds. But he can use words or actions to figure out our weaknesses and attack there.
Mt 12:34 O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh.
We are only as pure as our thoughts are pure.