Luke 6:45
A good man out of the good treasure of his heart bringeth forth that which is good; and an evil man out of the evil treasure of his heart bringeth forth that which is evil: for of the abundance of the heart his mouth speaketh.
Cross-reference
Luke 8:15 describes a good heart that bears fruit, mirroring how a good treasure produces good from the heart.
In Matthew 12:34-37, Jesus repeats the same teaching with identical wording, adding judgment for careless words.
Hebrews 8:10 shows God writing His law on hearts — the same internal source that Luke 6:45 says determines what we speak and do.
Colossians 4:6 commands gracious conversation, the outward result of a heart filled with grace.
Ephesians 5:4 directly addresses speech: no obscenity or coarse joking, consistent with a pure heart.
Ephesians 4:29 applies this principle: speech must build others up, reflecting a heart full of good.
2 Corinthians 4:7 uses the same treasure metaphor: treasure in jars of clay parallels treasure in the heart.
Matthew 12:34 gives the same teaching about heart abundance and speech with almost identical wording, reinforcing the principle across Gospels.
In Psalm 12:2-4, flattering lips and a double heart exemplify the evil treasure producing evil speech.
Psalm 64:3-8 describes tongues like swords shooting bitter words — a vivid picture of evil treasure producing evil speech.
Psalm 59:12 speaks of the sin of their mouth and lying words — the harvest of an evil heart's treasure.
Psalm 59:7 depicts enemies belching out swords with their mouths — evil speech flowing from an evil heart.
Psalm 52:2-4 portrays a tongue that devises deceit, loving evil — a clear parallel to the evil man's speech from evil treasure.
Psalm 41:6 describes one whose heart gathers iniquity while speaking vanity — directly illustrating the evil treasure and evil speech.
Psalm 40:8-10 has delight in God's will with law in heart, then declaring righteousness — directly mirrors heart's abundance overflowing into speech.
Matthew 23:26 calls for inner cleansing first, echoing that the heart's condition determines outward purity — same focus on inner treasure.
Proverbs 10:20 contrasts the righteous' valuable tongue with the wicked's worthless heart — directly linking heart quality to speech value.
Proverbs 10:21 says the lips of the righteous feed many — showing how a good heart's treasure nourishes others through speech.