This is my arm swinging and my alarm ringing
Fighting against time but writing is on
Singing the light on my wall or just look how the mighty have fallen
spent a lot of time listening to this lyric and I think what he actually says is “This is my arm swinging and my alarm ringing, Fighting against time but writing this song saying "In light of my wallet just look how the mighty have fallen”
The first part is the set up, his arm is swinging at his alarm, get it, he’s fighting against time. The reason he is fighting against time is to get this verse done.
Then he says, look at how much money he’s making, he’s doing better than a lot of the “mighty” (sarcasm) rappers of the past.
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