What does 1 Peter 1:5 mean?

In verses 3 and 4, Peter revealed that God has caused us to be born again to a living hope and a forever inheritance of limitless worth. Now he writes that the merciful God who gives us those great gifts is also actively guarding us, right in this moment.

Guarding us from what, suffering? No, as Peter will soon say, we will suffer. God is guarding our inheritance, and He is guarding us from anything that might cause our inheritance—our eternal life with Him forever—to be lost. The Greek term used in this verse is phrouroumenous, a military term, also translated as "shielded," "kept," or "protected."

We are being guarded by God's power. How powerful is God? How able is He? He is the God who created the universe. He is the God who raised Christ from the dead. He is the God of all. He is able. We are being guarded by God's power through faith. It's not our faith that is powerful. It is God. But it is a faith through which this relationship with God began and is maintained. We trusted Him to save, and we continue to trust that He will do everything necessary to keep us saved.

By God's grace, through faith, we have been saved (Ephesians 2:8–9), from the eternal penalty of our sin. We are being saved from the power of sin, growing more and more like Jesus. And, in this verse, Peter writes that we will be saved, even from the presence of sin, in Heaven. That is, our salvation will be fully revealed at just the right time. Until then, God guards us so that nothing can take that away.