“So mote it be”. Often abbreviated SMIB. Archaic for “So be it.” “Amen” comes from a Hebrew word meaning “truth”. So basically, saying Amen is saying “it is so.” Same with “So mote it be.”
“Blessed be” is often used at the end of certain ritual phrases, but it’s meaning is actually quite different from the meaning of “Amen”. “So mote it be” is much closer.
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