One of my youth pastors’ wives wrote a song when I was in high school that focused on the concept of our lives as Christians being totally centered around Christ. When she shared it with us one night, I remember her saying “let’s come back down to reality, though—does this really describe our lives?” In essence—this is a prayer—not something we have already perfectly attained. We still battle the flesh here on earth (Rom. 7:13-25). That we’d be “ever, only, all for Thee” is likewise a prayer that it would be so.
“I appeal to you therefore, brothers, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship.”