john 8:44 Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it. - Free Bible Online

      44. Ye are of your father the devil--"This is one of the most decisive testimonies to the objective (outward) personality of the devil. It is quite impossible to suppose an accommodation to Jewish views, or a metaphorical form of speech, in so solemn an assertion as this" [ALFORD].
      the lusts of your father--his impure, malignant, ungodly propensities, inclinations, desires.
      ye will do--are willing to do; not of any blind necessity of nature, but of pure natural inclination.
      He was a murderer from the beginning--The reference is not to Cain (as LOCKE, DE WETTE, ALFORD, &c.), but to Adam [GROTIUS, CALVIN, MEYER, LUTHARDT, &c.]. The death of the human race, in its widest sense, is ascribed to the murderous seducer of our race.
      and abode not in the truth--As, strictly speaking, the word means "abideth," it has been denied that the fall of Satan from a former holy state is here expressed [LOCKE, &c.], and some superior interpreters think it only implied [OLSHAUSEN, &c.]. But though the form of the thought is present--not past--this is to express the important idea, that his whole character and activity are just a continual aberration from his own original truth or rectitude; and thus his fall is not only the implied basis of the thought, but part of the statement itself, properly interpreted and brought out.
      no truth in him--void of all that holy, transparent rectitude which, as His creature, he originally possessed.
      When he speaketh a lie, he speaketh of his own--perhaps his own resources, treasures (Mt 12:35) [ALFORD]. (The word is plural). It means that he has no temptation to it from without; it is purely self-begotten, springing from a nature which is nothing but obliquity.
      the father of it--that is, of lying: all the falsehood in the world owes its existence to him. What a verse is this! It holds up the devil (1) as the murderer of the human race; but as this is meant here in the more profound sense of spiritual death, it holds him up, (2) as the spiritual parent of this fallen human family, communicating to his offspring his own evil passions and universal obliquity, and stimulating these into active exercise. But as there is "a stronger than he," who comes upon him and overcomes him (Lu 11:21, 22), it is only such as "love the darkness," who are addressed as children of the devil (Mt 13:38; 1Jo 3:8-10).

JFB.