When we get to Heaven we will have no sinful thoughts, words or actions. Our thought life will be perfected.
Revelation 21:27a And there shall in no wise enter into it any thing that defileth,
But we need to work on our thought life and ask for God’s help here and now. Our thought life is important to Him. We ought to put Him in charge of our thoughts. When He is in charge of our thoughts, He also works on our words and actions.
2 Corinthians 10:5 Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ;
Philippians 4:8 Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, 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.
Proverbs 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.
When we receive Christ, He purifies our hearts AND renews our minds.
Philippians 2:5 Let this mind be in you, which was also in Christ Jesus:
Romans 12:1 I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service. 2 And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.