How do we know that grace is unconditional in sovereign grace theology?

In the framework of sovereign grace theology, the unconditional nature of God's grace is affirmed through passages like Ephesians 2:8-9, where it states that salvation is a gift of God, not a result of works. This signifies that grace cannot be earned or deserved; rather, it emanates from God's benevolent will. The doctrine of election further emphasizes this, highlighting that those who are saved are chosen not for their deeds but solely out of God's magnanimity. This understanding brings believers assurance that their standing before God is entirely dependent upon His grace.