fun. – One Foot lyrics

I think this song has to do with the idea of religion and how he wants to believe in the idea of an afterlife, but for right now, all he can do is keep living his life the way he sees fit. Also, he seems frustrated with the blind beliefs that so many hold and contradict on a daily basis. He'd rather be true to his beliefs, even if it means, "sinning," and acknowledging it.

First a correction:.
To my left is a window, where did I go.
My reflection just planted two rows of coal (it is my reflection just blended into rows of coal) listen close, voice 1 - my reflection just blended, voice 2 - into rows of coal.
Second correction: it's not "happiness stumbled upon a chapel last night", it is "i happened to stumble upon a chapel last night".
This is obviously taking a stab at christian religion (before you bible thumpers start to thump, note that I highlighted religion or more so religiosity that so many of you liars let your churches turn into.
Very strait forward and quite literal:.
Afterall, afterall I thought we were all your children (christians are told that they are god's children).
But I will die for my own sins, thanks a lot (jesus came to earth to die for our sins, here he says "thanks a lot" sarcastically saying he doesn't need redemption through christ).
We'll rise up ourselves, thanks for nothing at all (mocking the fact that jesus rose from the grave, and promised he would raise all those who trust in him).
So up off the ground, our forefathers are nothing but dust now (speaking here more to catholics and other secs that kneel and pray to saints, mary, and jesus. Get up off the church floor, they're dead and gone and dust).
I'll put one foot in front of the other one.
I don't need a new love, or a new life.
Just a better place to die (this speaks to when you become "saved" jesus/god become your new love, and give you a new life in him, I. E. Born again. He's saying he doesn't need jesus and/or god to save him and give him a new love or give him a new life, he just wants the world to be a better place to die in).
Also it's not a homosexual-specific reference to "friends locked in boxes", look at their interviews on utube, they specifically say that they don't know why they have such a "queer" following, and that their songs are general in nature and not specific to homosexuality or homophobia.
When he says, regarding his father, "been fighting all his life", his parents were religious and against what he ended up "doing" and what he "believes", this is quite apparent across many of the songs on this lp.