'Sealed It' in the Bible

He wrote [a decree] in the name of King Ahasuerus, and sealed it with the king’s ring, and sent letters by couriers on horseback, riding on the royal [mail] relay horses, the offspring of the racing mares.

I signed the deed and sealed it, and called in witnesses, and weighed out the money on the scales.

A stone was brought and laid over the mouth of the den; and the king sealed it with his own signet ring and with the signet rings of his nobles, so that nothing would be changed concerning Daniel.