Jamieson, Fausset and Brown on 2 Peter 2:14

14. full of adultery--literally, "full of an adulteress," as though they carried about adulteresses always dwelling in their eyes: the eye being the avenue of lust [Horneius]. Bengel makes the adulteress who fills their eyes, to be "alluring desire."

that cannot cease--"that cannot be made to cease from sin."

beguiling--"laying baits for."

unstable--not firmly established in faith and piety.

heart--not only the eyes, which are the channel, but the heart, the fountain head of lust. Job 31:7, "Mine heart walked after mine eyes."

covetous practices--The oldest manuscripts read singular, "covetousness."

cursed children--rather as Greek, "children of curse," that is, devoted to the curse. Cursing and covetousness, as in Balaam's case, often go together: the curse he designed for Israel fell on Israel's foes and on himself. True believers bless, and curse not, and so are blessed.