Although it doesn't really fit the rest of the song, the line "who the cap fit, let them wear it" just has to mean that let people be who they will be, as Marleyfan says.
It's almost two sides of the coin. The advice is
1) who the cap fit, let them wear it. Leave others to themselves (don't be the hypocrite or liar).
2) don't just expect the same treatment from others. Trust has to be built, and should not be expected.
Although it doesn't really fit the rest of the song, the line "who the cap fit, let them wear it" just has to mean that let people be who they will be, as Marleyfan says.
It's almost two sides of the coin. The advice is 1) who the cap fit, let them wear it. Leave others to themselves (don't be the hypocrite or liar).
2) don't just expect the same treatment from others. Trust has to be built, and should not be expected.