For the sin of their mouth and the words of their lips; rather, the sin of their mouth is each word of their lips (Hupfeld, Cheyne); or, O the sin of their mouth! O the word of their lips! (Ewald, Kay, Canon Cook).
Let them even be taken in their pride. Saul's special emissaries (1 Samuel 19:11) would, of course, be proud of their mission. And for cursing and lying which they speak (comp. Psalms 10:7; and, for an example, see 2 Samuel 16:5-8).