Control your thoughts

“We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ.” (2 Cor. 10:5 NASB)

Your mouth speaks from what fills your heart  

“The good man out of the good treasure of his heart brings forth what is good; and the evil man out of the evil treasure brings forth what is evil; for his mouth speaks from that which fills his heart.” Luke 6:45 NASB)

Be transformed by renewing your mind

“And do not be conformed to this world, but be transformed by the renewing of your mind, so that you may prove what the will of God is, that which is good and acceptable and perfect.” (Rom. 12:2 NASB)

Prepare your mind for action

“Therefore, prepare your minds for action, keep sober in spirit, fix your hope completely on the grace to be brought to you at the revelation of Jesus Christ.” (1 Peter 1:3 NASB)

Therefore…

“Be anxious for nothing, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all comprehension, will guard your hearts and your minds in Christ Jesus.” (Phil. 4:6-7 NASB)