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Leasing
Leasing [EBD]
(Ps. 4:2; 5:6) an Old English word meaning lies, or lying, as the Hebrew word kazabh is generally rendered.
Leasing [NAVE]
LEASING, falsifying, Psa. 4:2.LEASING [SMITH]
(falsehood). This word is retained in the Authorized Version of (Psalms 4:2; 5:6) from the older English versions; but the Hebrew word of which it is the rendering is elsewhere almost uniformly translated "lies." (Psalms 40:4; 58:3) etc.LEASING [ISBE]
LEASING - lez'-ing (kazabh "to devise," "to fabricate," hence, "to lie"; occurs but twice in the King James Version (Ps 4:2, the Revised Version (British and American) "falsehood"; 5:6, the Revised Version (British and American) "lies"); the Hebrew word is translated "liars" (Ps 116:11); "lie" or deceive (Job 6:28)): The idea of treachery, lying, and deceit, lies at the root of this word. Joab's conduct is a good illustration of the meaning (2 Sam 3:27; 20:8-10). In Ps 5:6 David is referring to the cunning, treachery, and falsehood of his adversaries; compare 2 Sam 13:28; 15:7-9. Doubtless David had a special person in mind as being guilty of "leasing," probably Ahithophel.William Evans
Also see definition of "Leasing" in Word Study