Posture Affects Perspective

Sitting up straight makes you more confident:

Specifically, participants were asked to think about and write down their best or worse qualities while they were sitting down with their back erect and pushing their chest out (confident posture) or slouched forward with their back curved (doubtful posture). Then, participants completed a number of measures and reported their self-evaluations. In line with the self-validation hypothesis, we predicted and found that the effect of the direction of thoughts (positive/negative) on self-related attitudes was significantly greater when participants wrote their thoughts in the confident than in the doubtful posture.

It seems logical to take this in the opposite direction as well. Perhaps praying in a submissive position, kneeling or bowing, will make you feel more humble.