Pushin' on

Swing high, swing low
Swing it down til you hit the floor,
Find a crack and rip it,
Crawl through and you're reborn.

But don't stop there,
You might as well keep pushin' on.

Bring a light for comfort,
I'm not sure how much good it'll do,
Keep it up and keep up,
Keep it up til you reach the core.

I have absolutely no idea what I'm looking for,
but I'm willing to wager that no-one does.