Four Types of Klipos

The klipos are divided into four categories: jealousy, lust, honor, and athiesm. Jealousy is the klipa of Esav and this was rectified by Avraham Avinu; lust is the klipa of Yishmael and this was rectified by Yitzchok Avinue; honor is the klipa of Amalek and this was rectified by Yaakov Avinu; athiesm is the klipa of Gog and Magog--this will be rectified by Moshiach.

The first three types correspond to the three meals of Shabbos; and athiesm corresponds to the meal of Melave Malka, which is the meal of Dovid Malka Mashicha.

Pri Tzadik, Bereshis 1:2