'Smooth' in the Bible

For there is no stability in their mouth. Their heart is mischiefs, An open grave is their throat, Their tongue they make smooth.

Everyone says false words to his neighbour: their tongues are smooth in their talk, and their hearts are full of deceit.

The smooth lips and the tongue of pride will be cut off by the Lord.

For he made it smooth to himself in his eyes, To find his iniquity to be hated.

His buttery words are smooth,but war is in his heart.His words are softer than oil,but they are drawn swords.

You make the ploughed lands full of water; you make smooth the slopes: you make the earth soft with showers, sending your blessing on its growth.

How smooth [are] your words to my palate, more than honey in my mouth.