I have zero argument with John.
His first epistle is what I rely upon for clear revelation of Yeshua’s Way.
Those that do so will know that they have eternal life, because they keep all of Yeshua’s words, all of his Torah, because he has written it on their hearts.
That is exactly what John is saying in 1John 5:13.
Ah you Law Keepers!
I hope it works out for you...