The former regulation is set aside because it was weak and useless  (for the law made nothing perfect), and a better hope is introduced, by which we draw near to God.
Levitical law was useful for setting a perfect standard by which to gauge oneself. It was useful to know what sin was. But, even if it were possible to follow the laws perfectly, it was useless to draw one closer to God. Jesus’ grace and following Him (the new priest) is the only way to grow closer to God.
Many who are striving to live a good Christian life, may be living somewhat legalistically, apart from the true grace of Jesus and building a relationship with Him. Checking the legalistic boxes does not mean a person is trying to be more like Jesus, in obedience and reverence of Him. I worry that a person in this condition, may believe they are heading for heaven, but may not even know Jesus at all and be marching toward a path to hell. Let us not be one who hears on judgement day “I never knew you. Away from me, you evildoers!” (Mat 7:23).
Lord, thank You for choosing me. I know I’ll never be perfect but help me to be more and more like You. Lord I choose to follow You. To be more like You as I grow and to always honor You, be obedient to You, and glorify You in all I do. Help me when I waiver from this. In Jesus’ holy name I pray, amen.