That is, herein consists the judgment. The prefacing a statement with this is, and then defining the statement by ὅτι or ἵνα, that, is characteristic of John. See Joh 15:12; Joh 17:3; 1Jo 1:5; 1Jo 5:11, 1Jo 5:14; 3Jo 1:6.
Light (τὸ φῶς)
Rev., correctly, the light. See Joh 1:4, Joh 1:9.
Men (οἱ ἄνθρωποι)
Literally, the men. Regarded as a class.
Darkness (τὸ σκότος)
See on Joh 1:5. Rev., correctly, the darkness. John employs this word only here and 1Jo 1:6. His usual term is σκοτία (Joh 1:5; Joh 8:12; 1Jo 1:5, etc.), more commonly describing a state of darkness, than darkness as opposed to light.
Were (ἦν)
Habitually. The imperfect tense marking continuation.