1 John 2:4

4 The one who says, "I have come to know Him," without keeping His commands, is a liar, and the truth is not in him.

1 John 2:4 Meaning and Commentary

1 John 2:4

He that saith I know him
God or Christ, as the Gnostics did, who pretended to great, even perfect, knowledge of divine things:

and keepeth not his commandments;
which the above persons had no regard to, and as many who profess great light and knowledge in our days show no concern for:

is a liar;
he contradicts what he says, and gives the lie to it; for though in words he professes to know God, in works he denies him, and which betrays his ignorance of him:

and the truth is not in him;
there is no true knowledge of God and Christ in him; nor is the truth of the Gospel in his heart, however it may be in his head; nor is the truth of grace in him, for each of these lead persons to obedience. The Ethiopic version renders it, "the truth of God is not with him"; (See Gill on 1 John 1:8).

1 John 2:4 In-Context

2 He Himself is the propitiation for our sins, and not only for ours, but also for those of the whole world.
3 This is how we are sure that we have come to know Him: by keeping His commands.
4 The one who says, "I have come to know Him," without keeping His commands, is a liar, and the truth is not in him.
5 But whoever keeps His word, truly in him the love of God is perfected. This is how we know we are in Him:
6 the one who says he remains in Him should walk just as He walked.
Holman Christian Standard Bible ® Copyright © 2003, 2002, 2000, 1999 by Holman Bible Publishers.  Used by permission.  All rights reserved.