Hbr 8:11 And they shall not teach every man his neighbour, and every man his brother, saying, Know the Lord: for all shall know me, from the least to the greatest.
Hbr 8:12 For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
That is not for today, that is for the Millennium. No one is told today not to teach about the Lord. All of the chapter has to read as one promise, not just particular verses.
It isn't for today, it is for the Jew who is saved and enters into the Millennium Kingdom.
That of course is a heresy for it nullifies power of the cross and the gospel which declares us the righteousness of God and our likeness to Jesus Christ NOW. Those Biblical declarations about us are impossible if God still sees us as unrighteous and still remembers our sins. Your doctrine makes Christ of no effect whose blood washes ALL our sin away and CLEANSES US FROM ALL UNRIGHTEOUSNESS.