Tikkun #16 continue
The sin of Adam and Eve brought mortality to them and the whole world. Part of the correction process to this is that the woman has the Mitzvah of making Challah for Shabbat. She needs to separate a small piece from the dough, which represents the light of the upper three Sefirot that was lost because of the sin.
Another corrective action is the lighting of the candles before Shabbat to draw the upper light to make unification of Binah and Malchut.
Friday night is the best time for a man and a woman to unify with love. When connecting with love and spiritual consciousness, it bring them closer to each other and draws the light of Binah through the man that represents Zeir Anpin to Malchut. This unification also draws from the original blessing that God gave Adam and Eve on Friday, the day they were created.