Why do Freemasons end their prayers with the phrase “So mote it be”?

This article was originally written by Brother Rich Williams, of Drytown Lodge #174
Why do Freemasons end their prayers with the phrase “So mote it be”?
It is customary in contemporary English to end prayers with a hearty “Amen,” a word meaning “So be it.” Amen is derived from a Hebrew word, meaning “certainly.” Thus, a congregation saying “Amen” is literally “So be it be.” The word mote is an archaic verb that means “may” or “might,” and traces back to Old English. The phrase “So mote it be” means “So may it be,” which is the same as “So be it.” Now that we’ve established the equivalence of “Amen” and “So mote it be,” the question remains, “Why do Masons end their prayers with “So mote it be’ rather than just saying Amen?”
The answer goes back to the Regius Poem of about 1390 AD, the oldest known Masonic document (now housed in the British Museum, London). It is one of the Old Charges or Gothic