Keil & Delitzsch

Then in his boundless carnal security he gives free course to his wicked tongue. That which the believer can say by reason of his fellowship with God, בּל־אמּוט (Psa 30:7; Psa 16:8), is said by him in godless self-confidence. He looks upon himself in age after age, i.e., in the endless future, as אשׁר לא ברע, i.e., as one who (אשׁר as in Isa 8:20) will never be in evil case (ברע as in Exo 5:19; Sa2 16:8). It might perhaps also be interpreted according to Zac 8:20, Zac 8:23 (vid., Kצhler, in loc.): in all time to come (it will come to pass) that I am not in misfortune. But then the personal pronoun (אני or הוּא) ought not be omitted; whereas with our interpretation it is supplied from אמּוט, and there is no need to supply anything if the clause is taken as an apposition: in all time to come he who.... In connection with such unbounded self-confidence his mouth is full of אלה, cursing, execratio (not perjury, perjurium, a meaning the word never has), מרמות, deceit and craft of every kind, and תּך, oppression, violence. And that which he has under his tongue, and consequently always in readiness for being put forth (Psa 140:4, cf. Psa 66:17), is trouble for others, and in itself matured wickedness. Paul has made use of this Psa 10:7 in his contemplative description of the corruptness of mankind, Rom 3:14.