Sealed it. — This sealing both by the king and his nobles appears to have been due to the fear that the nobles had (Daniel 6:16) of the king’s attempting to rescue Daniel. The nobles also would be unable to put Daniel to death in the event of his escaping the fury of the lions.
Related Commentaries of Daniel 6:17
Daniel 6:17
17 And a stone was brought, and laid upon the mouth of the den; and the king sealed it with his own signet, and with the signet of his lords; that the purpose might not be changed concerning Daniel.