Proverbs 26:28

A tongue of deceit hates its victim, and a flattering mouth makes ruin.

Proverbs 29:5

A strong man who flatters his neighbor is spreading a net for his feet.

Proverbs 6:24

[in order] to preserve you from an evil woman, from the smoothness of [the] tongue of {an adulteress}.

Proverbs 7:5

[In order] to guard yourself from {an adulteress}, from the foreigner who {makes her words smooth}.

Proverbs 7:21-23

She persuades him with the greatness of her teachings; with her smooth lips she compels him.

Luke 20:20-21

And they watched [him] closely [and] sent spies who pretended they were upright, in order that they could catch him in a statement, so that they could hand him over to the authority and the jurisdiction of the governor.

John 8:40

But now you are seeking to kill me, a man who spoke to you the truth which I heard from God. This Abraham did not do.

John 8:44-49

You are of your father the devil, and you want to do the desires of your father! That one was a murderer from the beginning, and does not stand firm in the truth, because truth is not in him. Whenever he speaks the lie, he speaks from his own [nature], because he is a liar and the father {of lies}.

John 10:32-33

Jesus answered them, "I have shown you many good deeds from the Father. For which one of them are you going to stone me?"

John 15:22-24

If I had not come and spoken to them, they would not have sin. But now they do not have a valid excuse for their sin.

Treasury of Scripture Knowledge

Summary

A lying tongue hateth those that are afflicted by it; and a flattering mouth worketh ruin.

Bible References

A flattering

Proverbs 6:24
[in order] to preserve you from an evil woman, from the smoothness of [the] tongue of {an adulteress}.
Proverbs 7:5
[In order] to guard yourself from {an adulteress}, from the foreigner who {makes her words smooth}.
Proverbs 29:5
A strong man who flatters his neighbor is spreading a net for his feet.
Luke 20:20
And they watched [him] closely [and] sent spies who pretended they were upright, in order that they could catch him in a statement, so that they could hand him over to the authority and the jurisdiction of the governor.

General references

Judges 16:6
So Delilah said to Samson, "Please tell me what makes your strength so great, and with what can you be tied up to subdue you?"
1 Samuel 24:9
Then David said to Saul, "Why do you listen to the words of people who say: 'Look, David [is] {seeking to do you harm}'?
Ezekiel 12:24
For [there] will not be any longer {any false vision} or flattering divination in the midst of the house of Israel.