How do we know salvation is assured according to the Reformed perspective?

From the Reformed perspective, the certainty of salvation is grounded in God's immutable nature. He cannot lie, which means everything He has promised regarding salvation will surely come to pass. The foundation of our salvation rests on the finished work of Christ, as proclaimed in Scripture. In Ephesians 1:4, it states that God chose us in Him before the foundation of the world, confirming the eternal aspect of His grace and purpose in our lives. Our salvation is not based on our works but solely on God's promise and Christ's redemptive act, assuring us that those whom He has chosen will come to faith and be saved.