[21:26] 1 tn According to L&N 23.184 this could be mainly a psychological experience rather than actual loss of consciousness. It could also refer to complete discouragement because of fear, leading people to give up hope (L&N 25.293).
[21:26] 2 sn An allusion to Isa 34:4. The heavens were seen as the abode of heavenly forces, so their shaking indicates distress in the spiritual realm. Although some take the powers as a reference to bodies in the heavens (like stars and planets, “the heavenly bodies,” NIV) this is not as likely.