Lyric discussion by SnareRushJunkie 

And your skin tastes much better with aging Not sweet like it was back in our Sunday school.

Are such beautiful lines. To me, it's symbolic of the maturing of his faith. He's realized that there is more to God than the good feelings that came when he was first a Christian. Faith is a very difficult thing, but it's only through difficulties that it can become stronger. It also brings to mind the part of Revelation were John writes about eating a scroll that God had given him, and how it was "in [his] belly bitter, but in [his] mouth it was sweet".

Overall, I guess the song is about growing up, both in age and in faith, how he knows he's messed up and strayed, but that has given him a better view of what it really means to follow God. He's asking God to take him back again, and he desires to grow further still.

I agree with this interpretation.

It's like at first he's saying he doesn't understand Jesus very much, so he'll hold his opinions of Him and try to just believe. At this point he's innocent and naive. [I'm biased and by this I'll judge you on weakness wrapped up in my own innocence]

But as he gets older, through triumph and failure he discovers what it means to need God's grace [skin tastes much better with aging...], and begins to understand the backwards manner that the world looks at Jesus' life and mission [from mirrors you looked like a fool]

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