The Gospel and Prayer
Speaking loosely, I've begun to find that prayer is the most important means of living the Gospel.
This is because my understanding of the Gospel is that the human experience is the quest for deliverance from Evil, and the good news is that God, in his perfect capacity, acts to deliver us from evil. Our role is almost a passive one, except that we are to simply believe that God is, in fact, acting to save us.
And prayer is the perfect way to experience this. By making a petition to God, we acknowledge our need (or, in other words, it's an act of repenting from the sin of self-sufficiency, aka, believing we can save ourselves, aka, believing that we are God). In that act, we also are expresssing our faith that God can and will save us. And then we wait on God, in His infinite wisdom and capacity, to answer, knowing that either He will do as we've prayed, or else it wouldn't have been good for us if He had.