首楞嚴義疏注經 2.76

2.76

Since he said erecting the arm is upright, the Buddha then erected his arm and immediately reproached him: this is precisely inverted. The fingers fundamentally hang down; now they point upward conversely; hence he speaks of 'a reversal of top and bottom.' Worldly people do not rely on the fundamental state to take upright as upright, but generate aberrant views to take inverted as upright; hence he says they 'double their gaze.'