God, through the prophet Isaiah, calls Israel to account for performing religious rituals. However impressive this is, it conceals an empty heart and a careless life (Is 1:10-17). This is a rebuke to people who keep the form of godliness but deny its power (2 Tim 3:5). The way God's people lived was far away from God, so He had an invitation for them to turn back to Him (repent) and He would receive them and cleanse them. With God, judgement is never the last word. Jesus is offering a better covenant.