dingodad:

Equius seems to be using ‘STRENGTH’ in this case to allude to nobility, rank and leadership, which makes sense because it’s kind of his thing; society is controlled by the strong in his eyes and in the Alternian mind in general.

When Dave denies being strong, he denies that he’s the King Arthur figure that SBURB wants him to be, which is why John shares the Heir class with Equius and Dave has a serving class instead. Davesprite even alludes to this directly in the very next conversation:

DAVESPRITE: maybe if john was to try with his pure heart and shit it woulda popped out like a champagne cork and fuckin hero confetti woulda blasted him in the face
DAVESPRITE: but you
DAVESPRITE: we
DAVESPRITE: we had to break it

What broken weapons have to do with being King, though, I’m not quite sure.

(in reference to this exchange)