Well, I know it's about Josh Farro, but personally, I think that in general it's about self-righteous people who always blame others for everything, never taking any blame for themselves. Therefore, those people are basically classifying themselves as perfect, but only God is perfect, therefore, they're "Playing God."
"Because it has to be so lonely to be the only one who's holy."
^ I think that's Hayley describing how Josh would be casting the blame on everyone else (mostly her) during the BNE era, and あなた can tell によって 読書 his exit blog and watching their "Last Word." It sounded like he would basically slap her with a Bible when she came up with a lyric he didn't like, even though she's a Christian as well. He was the one 芝居 "holy" in that sense, and "Playing God" as in playing that whole Bible game in order to blame her. In the Last Word, Taylor describes how Hayley meant something totally different than Josh thought with those lyrics, but apparently he never let it go. In his blog, he never once blamed himself for one little thing (that I can remember anyway), so again, it's back to that whole self-righteous thing.
Heh... sorry if none of that made sense. I have a huge, personal attachment to this song, but I don't really know how to describe it in words.