金剛經纂要刊定記 3.176

3.176

恭敬者。總結也。起座袒肩、跪膝合掌，莫非恭敬故爾，亦可配於三業。謂座起袒肩合掌等身業也，恭敬即意業也，白佛言下即口業也。

On "respectful": a concluding summary. Rising from the seat, baring the shoulder, kneeling, and joining palms—none of these is not respectfulness, hence this is stated. They may also be correlated with the three karmas: rising from the seat, baring the shoulder, and joining the palms are bodily karma; respectfulness is mental karma; and "addressed the Buddha, saying" and what follows is vocal karma.