What the Bible says about guarding the heart

1 Peter 5:8

Be sober and self-controlled. Be watchful. Your adversary, the devil, walks around like a roaring lion, seeking whom he may devour.

2 Timothy 2:22

Flee from youthful lusts; but pursue righteousness, faith, love, and peace with those who call on the Lord out of a pure heart.

Psalm 141:3-4

Set a watch, Yahweh, before my mouth. Keep the door of my lips. Don’t incline my heart to any evil thing, to practice deeds of wickedness with men who work iniquity. Don’t let me eat of their delicacies.

James 4:7-8

Be subject therefore to God. Resist the devil, and he will flee from you. Draw near to God, and he will draw near to you. Cleanse your hands, you sinners; and purify your hearts, you double-minded.

Proverbs 14:12

There is a way which seems right to a man, but in the end it leads to death.

Matthew 12:34-35

You offspring of vipers, how can you, being evil, speak good things? For out of the abundance of the heart, the mouth speaks. The good man out of his good treasure brings out good things, and the evil man out of his evil treasure brings out evil things.

Colossians 3:2

Set your mind on the things that are above, not on the things that are on the earth.

Proverbs 23:7

for as he thinks about the cost, so he is. “Eat and drink!” he says to you, but his heart is not with you.

1 John 4:7

Beloved, let us love one another, for love is of God; and everyone who loves has been born of God, and knows God.