395. Anyone who kills Cain will suffer sevenfold vengeance means there was a sacred ban on violating the faith detached in this way. This is established by the symbolism of Cain as a detached faith and of seven as a sacred ban.
The number seven was held sacred, as is known, 1
because of the six days of creation and because of the seventh day — which is the heavenly kind of person — on which there is peace, repose, a Sabbath. This is why the rituals of the Jewish religion so often involve the number seven, and each time it is seen to stand for something sacred. 2
For this reason, different stretches of time, long and short, were divided in seven and called weeks. One instance is the long periods before the coming of the Messiah in Daniel 9:24-25. Laban and Jacob call a period of seven years a week in Genesis 29:27-28. So wherever the number seven occurs, it is considered as standing for something sacred, or else for a sacred ban, as in David:
Seven times in a day do I praise you. (Psalms 119:164)
In Isaiah:
The light of the moon will be like the light of the sun, and the light of the sun will be seven times as strong, like the light of seven days. (Isaiah 30:26)
Here the sun is love and the moon is faith from love, which will be like love.
[2] Just as the stages of a person's regeneration are divided into six, which precede the seventh, or the stage of being heavenly, so too are the stages of devastation, which continues until nothing heavenly remains. This was represented by the Jews' many captivities, including the last, in Babylon — a captivity of seven "ages" or seventy years; 3
and several times it is said that the land was to rest during its Sabbaths. 4
Devastation was also represented by Nebuchadnezzar in Daniel:
His heart will change from [that of] a human, and the heart of an animal will be given to him, until seven seasons change upon him. (Daniel 4:16, 25, 32)
Concerning the devastation of the final days as described by John:
I saw another sign in the sky, great and awesome: seven angels having the seven final plagues. (Revelation 15:1, 6-7)
Revelation 11:2 says that the holy city will be trampled for forty-two months, which is six times seven. In the same author:
I saw a book written inside and on the back, 5
sealed with seven seals. (Revelation 5:1)
Accordingly, different severities and levels of punishment were expressed in sevens, as in Moses:
If after all this you do not obey me, I will castigate you seven times harder for your sins. (Leviticus 26:18, 21, 24, 28)
In David:
Return seven times as much into our neighbors' lap. (Psalms 79:12)
Since a sanction was placed on the violation of faith, then, because faith could be of service (as has already been said [§372]), the present verse states that the person who kills Cain will suffer sevenfold vengeance.
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