ANSWER: According to John's definition of sin, "sin is lawlessness," it may refer to either. Here it is quite evident that it refers to a state. In the next verse the phrase, "have sin," is peculiar to John, and it always implies an act entailing guilt. See John 9:41; 15:22, 24; 19:11. Another peculiarity of John is that he does not trace sin along the line of heredity up to Adam, as Paul does, but he ascribes it to the devil. "He that committeth sin is of the devil." In this particular John imitates Christ, who emphasizes not so much the source of sin as its guilt and. its cure; not the origin of the conflagration, but how to put it out. John does not contradict Paul; he only traces sin one step further back to the first sinner in the universe.
— Steele's Answers p. 132.