American Gospel
I don't know what the gospel must mean to those in other countries. But in America, I believe the gospel message is: quit being anxious and know that God loves you. Trust him and enjoy him. Depend on him and not on yourself.
God is selfish. He wants you to know how much you need him (and you do, even though most of the time you forget).
We only feel and experience his abundant blessings when we realize how much we need him. To get there, we have to realize our weakness and his strength. It's really simple, but really hard.