Quotation for Beitzah 31:9

It is in allusion to what we have just said that the Rabbis say, “All agree that the Torah was given to Israel on the Sabbath.” The meaning is, it was given on the Sabbath as an indication that by means of it a person can acquire an intellect produced by the quality called Sabbath, which has independent existence. This is the additional soul or oversoul of which the Rabbis say that it is given to man on the Sabbath and taken away from him at the close of Sabbath, in accordance with the expression, “Ceased from work and rested,” which they interpret, by a play upon the Hebrew words, “Alas! the soul has gone.”