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.
The Church is never under a Covenant.
The Blood atonement is mentioned throughout the Epistles (Eph.1:7, Col.1:14).
You are reading a Bible with the Old and New Testaments, not the Old and New Covenants.