A common misinterpretation is to take this verse as a rejection of all Scripture or written law in favor of subjective personal feelings or 'spiritual intuitions,' suggesting the Bible itself is the deadly 'letter' to be discarded; another error is antinomianism, claiming moral laws are entirely obsolete and sin has no consequences under grace, ignoring that Paul contrasts the old covenant's condemning ministry with the new covenant's life-giving one through the Spirit, without abolishing God's ethical standards.
II Corinthians 3:6
King James Version (1769)
6 Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.
Paul declares that God has qualified him and his fellow apostles as ministers of the new covenant, which is characterized by the Spirit rather than the mere letter of the law. The core truth here is the superiority of the new testament, where the 'letter'—rigid, external observance of the Mosaic law—brings death by exposing sin without providing power to overcome it, while the 'spirit' of the gospel, empowered by the Holy Spirit through Christ, imparts transformative life and righteousness to believers.