How does God show grace to those who are unworthy?

In the biblical narrative, God's grace is shown through His mercy towards those deemed unworthy. David exemplifies this as he was chosen despite his significant failings. Romans 9:15 states, 'For he saith to Moses, I will have mercy on whom I will have mercy, and I will have compassion on whom I will have compassion.' This indicates God's sovereign will in the distribution of grace. The core of sovereign grace is that it is not our good works that earn us favor, but rather God's mercy to save individuals who, like David, are often flawed and sinful.