My version of John I 4:3 is as follows:
“and every spirit that acknowledges Jesus Christ come in the flesh belongs to God, and every spirit that does not acknowledge Jesus does not belong to God. This is the spirit of the antichrist that, as you heard, is to come, but in fact is already in the world.
The New America Bible. The words an meaning are the same, but it may be a bit clearer from the NAB.
Yeah, I just prefer the cadence of the KJV. It was intended to be read aloud, so it really has a strong rhythm to the verses that makes them memorable.