Abel הבל – vanity.
“These are the words of the Preacher, the son of David, king in Jerusalem.”
“Vanity of vanities, says the Preacher, vanity of vanities; all is vanity. “
Altogether, there are seven הבלים Abelim (vanities): vanity is one; vanities means at least two vanities, thus “Vanity of vanities” = three vanities. And he repeats again, “Vanity of vanities,” which makes six in total. By adding “all is – Abel הבל – vanity,” at the end, this gives us seven Abels or הבלים Abelim, vanities.
“What profit has a man (in klipoth) of all his labour which he takes under the sun? One generation passes away (in one level), and another generation comes (in the following level): and (the 7 purgatorial levels of) the earth abides for ever.”
“(Regarding sexual alchemy) The sun (Christ) also arises (from Yesod-sex), and the sun (Christ) goes down (from the Ain Soph Aur into Yesod-sex), and hastes to his place where he arose.” – Ecclesiastes 1: 1-5
“And Cain went out from the presence of Jehovah, and dwelt in the land of Nod (Limbo), on the east of Eden (Yesod).” – Genesis 4: 16
After repenting of the sin of fornication, Cain, by means of sexual alchemy, became reconciled with Jehovah in Eden (Yesod) and dwelt in the land of Nod, which is the first sphere of hell, named Limbo.