Lyric discussion by zia7 

Cover art for My Friend Marcus lyrics by Manchester Orchestra

I think it has to do with Andy's friend's spritual walk. He is having trouble accepting it at the beginning of the song and it's bothering him. Later in the song, Marcus is helping Andy with his spiritual walk.

"My friend Marcus, he works on a train set And I still can't move on my broke track He's helping me find my meaning Eventually and hopefully we'll see"

The train set could be Marcus' walk. Andy is stuck in life, and Marcus is helping Andy out.

"Its funny how many don't know How many dont have a home"

People that don't know Christ.

My take on the spirits part is that i think it references alcohol and that he touched more than alcohol so like other drugs and whatnot. Could be way off but that is how i interpret that part.