How do we know that God's grace is sovereign in our salvation?

Scripture explicitly states in Romans 9:16 that 'it is not of him that willeth, nor of him that runneth, but of God that showeth mercy.' This emphasizes that our salvation is entirely a result of God's sovereign grace rather than any human decision or action. God's grace is given freely and is not based on any conditions or merits in the recipient. This unearned grace illustrates God's mercy towards sinners, something all believers can rejoice in, as it highlights God's initiative and will in the redemption process, not our own.