Romans 3:13

Their throat is an open sepulchre — i.e., their speech is at once corrupt and corrupting. It is compared to a “yawning grave” — not merely to a pit into which a man may fall, but to a sort of pestiferous chasm yawning and ravening, as it were, after its prey.

They have used deceit. — Strictly, they were deceiving; a continued action brought up to the present time.

Under their lips. — As the poison-bag of the serpent is directly under the kind of tooth by which its venom is discharged.