The word to notice here is "quicken." God shall quicken, shall give life to "your mortal bodies." You say, "But I have life; I'm breathing." That is what most of us consider. We think, "Yes, of course I'm a sinner, but I'm alive, and now I just take Jesus..." But we don't realize that we were dead. Of course we know the theology that says so--but we need the response, now. We need the simplicity of a child's heart that Jesus spoke about. We must come as children. Not the religious way, but God's way--life.
If God is going to quicken, to give life to our mortal bodies by His Spirit that dwells in us, we can't bring along anything with us, from any source. Nothing's going to work here but God. You may say, "But what if God wants me to work?" God has already chosen to work in Christ Jesus. And He said, "Whosoever will, let him come." Are we willing to wait for the word of God?
Do we feel like Peter when he got out of the boat? Many times when we enter the realm of the Spirit, we begin, like Peter, to look around us at the circumstances. We begin again to depend on our natural reasoning, and the next thing we know we're sinking; we're turning around and grasping to get back into the boat, scrambling and splashing water, and we're afraid. Why should we be? Out on the water is where God wants us to walk--in the Spirit. This is the only place where the working of God takes place, the only place we can know victory over sin. It's the only place we can know the quickening power of the Holy Spirit.