Psalm 12:2

They speak vanity each one with his neighbor; with flattering lips and a double heart they speak.

Psalm 41:6

And when he comes to see me, he speaks vanity; his heart gathers iniquity to itself; he goes out and speaks of it.

Romans 16:18

For they who are such do not serve our Lord Jesus Christ, but their own belly; and by good words and fair speeches they deceive the hearts of the simple.

Psalm 10:7

His mouth is full of cursing and deceit and fraud; under his tongue are mischief and vanity.

Jeremiah 9:8

Their tongue is a slaughtering arrow; it speaks deceit; one speaks peaceably to his neighbor with his mouth, but in heart he lies in ambush.

1 Chronicles 12:33

From Zebulun, such as went forth to battle, expert in war, with all the weapons of war, fifty thousand who could keep rank. They were not of a double heart.

Psalm 5:9

For there is no faithfulness in their mouth; their inward part is wickedness; their throat is an open grave; they flatter with their tongue.

Psalm 28:3

Draw me not away with the wicked, and with the workers of iniquity, who speak peace to their neighbors, yet evil is in their hearts.

Psalm 144:8

because their mouth has spoken vanity, and their right hand is a right hand of lies.

James 1:8

he is a double-minded man, not dependable in all his ways.

Psalm 36:3-4

The words of his mouth are evil and deceit; he has stopped acting wisely and doing good.

Psalm 38:12

And those who seek my life lay snares for me; and those who seek my hurt speak sly things, and utter deceits all the day long.

Psalm 52:1-4

To the Chief Musician. A contemplation. A Psalm of David, when Doeg the Edomite came and told Saul, and said to him, David has come to the house of Ahimelech. Why do you boast yourself in evil, O mighty man? The mercy of God endures forever.

Psalm 55:21

The butterings of his mouth were forked, but war was in his heart; his words were softer than oil, yet they were drawn swords.

Psalm 59:12

For the sin of their mouth is the word of their lips, even let them be taken in their pride; and for cursing and the lying which they speak.

Psalm 62:4

Surely they have plotted to cast him down from his great height; they delight in lies; they bless with their mouth, but they curse in their heart. Selah.

Psalm 144:11

Rescue me, and deliver me from the hand of foreigners' sons, because their mouth has spoken vanity, and their right hand is a right hand of falsehood;

Proverbs 20:19

A gossip is a revealer of secrets; so do not mix with him who flatters with his lips.

Proverbs 29:5

A man who flatters his neighbor spreads a net for his feet.

Jeremiah 9:2-6

Oh that I had in the wilderness a lodging place for traveling men, that I might leave my people and go away from them! For they are all adulterers, an assembly of treacherous men.

Ezekiel 12:24

For there shall never again be any vain vision nor slippery divination within the house of Israel.

1 Thessalonians 2:5

For neither at any time did we use flattering words, as you know, nor with pretense of covetousness; God is witness.

Treasury of Scripture Knowledge

Summary

They speak vanity every one with his neighbour: with flattering lips and with a double heart do they speak.

A double heart

Bible References

Flattering

Psalm 5:9
For there is no faithfulness in their mouth; their inward part is wickedness; their throat is an open grave; they flatter with their tongue.
Psalm 28:3
Draw me not away with the wicked, and with the workers of iniquity, who speak peace to their neighbors, yet evil is in their hearts.
Psalm 62:4
Surely they have plotted to cast him down from his great height; they delight in lies; they bless with their mouth, but they curse in their heart. Selah.
Proverbs 20:19
A gossip is a revealer of secrets; so do not mix with him who flatters with his lips.
Proverbs 29:5
A man who flatters his neighbor spreads a net for his feet.
Ezekiel 12:24
For there shall never again be any vain vision nor slippery divination within the house of Israel.
Romans 16:18
For they who are such do not serve our Lord Jesus Christ, but their own belly; and by good words and fair speeches they deceive the hearts of the simple.
1 Thessalonians 2:5
For neither at any time did we use flattering words, as you know, nor with pretense of covetousness; God is witness.

A double heart

1 Chronicles 12:33
From Zebulun, such as went forth to battle, expert in war, with all the weapons of war, fifty thousand who could keep rank. They were not of a double heart.

General references

Genesis 29:19
And Laban said, It is better that I give her to you than that I should give her to another man. Stay with me.
Judges 16:6
And Delilah said to Samson, Please tell me where your great strength lies, and with what you may be bound to afflict you.
Habakkuk 1:3
Why do You show me evil, and You look on toil? For destruction and violence are before me; and there is strife, and contention rises up.
Acts 12:22
And the people gave a shout, saying, It is the voice of a god and not of a man!