These things have I written unto you concerning them that would lead you astray.
These things have I written unto you concerning them that seduce you.
I write this to you with reference to those who would deceive you [seduce and lead you astray].
I write these things to you about those who are attempting to deceive you.
I have written these things to you, because of those who would seduce you.
These things have I written to you, concerning them that seduce you.