"So mote it be" What is its translation?

I recently came across an Energy Summoning Spell on a website, and I was trying to translate it in Italian for practice. The spell is the following:

Energy i summon thee,

black to white,

dark to light,

i call to thee,

precious energy.

this is my will,

so mote it be.

I managed to translate basically everything:

Energia io ti invoco,

Dal nero al bianco,

Dal buio alla luce,

Io mi rivolgo a te,

Preziosa energia.

Questa è la mia volontà,

E cosí sia.

But there are some lines I'm not sure about, being:

i call to thee,

[. . .]

so mote it be.

This final line is even more complicated, as it's unclear what is supposed to say. According to a website, it's supposed to mean so may it be or so must it be. According to another website, it's supposed to mean, in italian, Sia fatta la volontà di Dio.