Grace is God's unmerited favor in which He shows us mercy, kindness, and patience instead of the judgment that we deserve for sinning against Him. God's grace cannot be earned by our actions/performance/works. Grace is based on the character of God and not on our sincerity, performance, or ability to keep the law. Otherwise, grace would not be grace.
Romans 11:6, "But if it is by grace, it is no longer on the basis of works, otherwise grace is no longer grace."
Galatians 2:21, "I do not nullify the grace of God; for if righteousness comes through the Law, then Christ died needlessly."
2 Timothy 1:9, "who has saved us, and called us with a holy calling, not according to our works, but according to His own purpose and grace which was granted us in Christ Jesus from all eternity."
God's grace (enabling power) operates sovereignly in the lives of believers.
1 Corinthians 15:10 - But by the grace of God I am what I am, and His grace toward me did not prove vain; but I labored even more than all of them, yet not I, but the grace of God with me.
2 Corinthians 1:12 - For our proud confidence is this: the testimony of our conscience, that in holiness and godly sincerity, not in fleshly wisdom but in the grace of God, we have conducted ourselves in the world, and especially toward you.
2 Corinthians 12:9 - And He has said to me, "My grace is sufficient for you, for power is perfected in weakness." Most gladly, therefore, I will rather boast about my weaknesses, so that the power of Christ may dwell in me.