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.

3 For I say, through the grace given unto me, to every man that is among you, not to think of himself more highly than he ought to think; but to think soberly, according as God hath dealt to every man the measure of faith.

4 For as we have many members in one body, and all members have not the same office:

5 So we, being many, are one body in Christ, and every one members one of another.

6 Having then gifts differing according to the grace that is given to us, whether prophecy, let us prophesy according to the proportion of faith;

7 Or ministry, let us wait on our ministering: or he that teacheth, on teaching;

Here is a post on the topic of the renewing of the mind.

https://harrisonhouse.com/blog/michelle-steele-dont-let-satan-direct-your-thoughts

Thoughts lead to words and words are very important.  At the bottom of each blog post there is a link that takes you to a page with resources.  Some of those links will connect you to teachings on the importance of words.

Numbers 14:28 (KJV) Say unto them, As truly as I live, saith the LORD, as ye have spoken in mine ears, so will I do to you:

Proverbs 18:21 Death and life are in the power of the tongue: and they that love it shall eat the fruit thereof.

Matthew 12:37  For by thy words thou shalt be justified, and by thy words thou shalt be condemned