The first thing we need to understand is we cannot save ourselves. Imagine being on a ship in the middle of the Atlantic Ocean and falling overboard. Because no one saw you fall in, the ship continues toward its destination, leaving you hopelessly stranded.
After treading water for several hours, you find yourself surrounded by sharks. You face certain death at any moment. Exhausted from trying to stay afloat, you slip underwater and begin to drown. Somehow, you force your way to the surface for one more gasp of air.
As you are about to go under for the last time, a helicopter appears miraculously out of nowhere. The rescue squad inside the helicopter throws out a rope and lassos your hand, pulling you out of the water just seconds before the sharks move in for the kill. The helicopter flies you back to shore, where you receive treatment in the hospital.
After you recover, you begin to brag about how you saved yourself. "I'm really proud of my hand. This hand saved me. Let me tell you how I found the helicopter in the middle of the ocean...."
Just like we can't save ourselves if we were stranded in the Atlantic, we are also helpless to save ourselves from hell. God doesn't want our help, either. Because Jesus does all of the saving, we have no right to brag about anything we have done.
"For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; not as a result of works, that no one should boast" (Ephesians 2:8-9).
(Kent Crockett, The 911 Handbook, Peabody, MA: Hendrickson Publishers, 2003, 221)