Cain Shall Be Protected for Seven שבעתים יוקם

The LORD said to him, "If so, the same shall be done for any who kills Cain. He shall be protected for seven." And placed the LORD upon Cain a mark, lest they strike him who do discover him.

בראשית ד׳:י״ג-ט״ו

(יג) וַיֹּ֥אמֶר קַ֖יִן אֶל־ה' גָּד֥וֹל עֲוֺנִ֖י מִנְּשֹֽׂא׃ (יד) הֵן֩ גֵּרַ֨שְׁתָּ אֹתִ֜י הַיּ֗וֹם מֵעַל֙ פְּנֵ֣י הָֽאֲדָמָ֔ה וּמִפָּנֶ֖יךָ אֶסָּתֵ֑ר וְהָיִ֜יתִי נָ֤ע וָנָד֙ בָּאָ֔רֶץ וְהָיָ֥ה כׇל־מֹצְאִ֖י יַֽהַרְגֵֽנִי׃ (טו) וַיֹּ֧אמֶר ל֣וֹ ה' לָכֵן֙ כׇּל־הֹרֵ֣ג קַ֔יִן שִׁבְעָתַ֖יִם יֻקָּ֑ם וַיָּ֨שֶׂם ה' לְקַ֙יִן֙ א֔וֹת לְבִלְתִּ֥י הַכּוֹת־אֹת֖וֹ כׇּל־מֹצְאֽוֹ׃

Genesis 4:13-15

(13) Cain said to the LORD, “My punishment is too great to bear! (14) Since You have banished me this day from the soil, and I must avoid Your presence and become a restless wanderer on earth—anyone who meets me may kill me!” (15) The LORD said to him, “I promise, if anyone kills Cain, sevenfold vengeance shall be taken on him.” And the LORD put a mark on Cain, lest anyone who met him should kill him.

תרגום אונקלוס על בראשית ד׳:ט״ו

וַאֲמַר לֵהּ ה' בְּכֵן כָּל קָטִיל קַיִן לְשַׁבְעָא דָּרִין יִתְפְּרַע מִנֵּהּ וְשַׁוִּי ה' לְקַיִן אָתָא בְּדִיל דְּלָא לְמִקְטַל יָתֵהּ כָּל דִיִשְׁכְּחֻנֵהּ:

Onkelos Genesis 4:15

And unto him the LORD said, "Therefore anyone may kill Qain (But) To seven generations let fruit be born of him.

תרגום יונתן על בראשית ד׳:ט״ו

וַאֲמַר לֵיהּ ה' הָא בְּכֵן כָּל דְקָטִיל קַיִן לְשִׁבְעָא דָרִין יִתְפְּרַע מִנֵיהּ וְרָשַׁם ה' עַל אַפֵּי דְקַיִן אָתָא מִן שְׁמָא רַבָּא וְיַקִירָא בְּגִין דְלָא לְמִקְטוֹל יָתֵיהּ כָּל דְיִשְׁכְּחוּנֵיהּ בְּאִסְתַּכְּלוּתֵיהּ בֵּיהּ

Targum Jonathan on Genesis 4:15

And the Lord said to him, Behold now, any one who killeth Kain, unto seven generations fruit shall be taken of him. And the Lord sealed upon the face of Kain the mark of the Name great and honourable, that any one who might find him should not kill him when he saw it upon him.

Targum Yonatan does not use Aramaic verb "vengeance" as implied by this inaccurate "translation", but rather פרע "be fruitful". A more correct English interpretation of the Aramaic would be "Unto seven generations they shall bear fruit from him." Onkelos, Yonatan agree on this interpretation, as does Rash"i later. There is no support in any of the sources for this utterly upside down mistranslation of יוקם "He shall stand" as "he shall be avenged", which is contrary to the plain sense of the hebrew language, to the general spirit of the Torah and its later elaboration at Sinai of "an eye for an eye", and to the unanimous reading of the early Aramaic Targums and the later Jewish commentators such as Rash"i

רש"י על בראשית ד׳:ט״ו:א׳

לכן כל הורג קין. זֶה אֶחָד מִן הַמִּקְרָאוֹת שֶׁקִּצְּרוּ דִּבְרֵיהֶם וְרָמְזוּ וְלֹא פֵרְשׁוּ, לָכֵן כָּל הֹרֵג קַיִן לְשׁוֹן גְּעָרָה, כֹּה יֵעָשֶׂה לוֹ, כָּךְ וְכָךְ עָנְשׁוֹ וְלֹא פֵּרֵשׁ עָנְשׁוֹ:

Rashi on Genesis 4:15:1

לכן כל הרג קין VERILY, WHOSOEVER SLAYETH CAIN — This is one of the verses where the construction is elliptical (literally, which abbreviate their statements), which give only a suggestion and do not fully explain. “Verily, whosoever slayeth Cain” express a threat, suggesting the consequence — “thus shall be done to him”, “thus and thus shall be his punishment”, without explicitly explaining what the punishment would be.

בראשית ד׳:כ״ג-כ״ד

(כג) וַיֹּ֨אמֶר לֶ֜מֶךְ לְנָשָׁ֗יו עָדָ֤ה וְצִלָּה֙ שְׁמַ֣עַן קוֹלִ֔י נְשֵׁ֣י לֶ֔מֶךְ הַאְזֵ֖נָּה אִמְרָתִ֑י כִּ֣י אִ֤ישׁ הָרַ֙גְתִּי֙ לְפִצְעִ֔י וְיֶ֖לֶד לְחַבֻּרָתִֽי׃ (כד) כִּ֥י שִׁבְעָתַ֖יִם יֻקַּם־קָ֑יִן וְלֶ֖מֶךְ שִׁבְעִ֥ים וְשִׁבְעָֽה׃

Genesis 4:23-24

(23) And Lamech said to his wives,
“Adah and Zillah, hear my voice;
O wives of Lamech, give ear to my speech.
I have slain a man for wounding me,
And a lad for bruising me. (24) If Cain is avenged sevenfold,
Then Lamech seventy-sevenfold.”

Midrash: conversation between Adam How'd it go? and Cain: describing his temporary clemency before the judgement of "life for a life", will be rendered to him as punishment. Noting this, Adam responds: "I should have done teshuvah instead of blaming the woman"

Rash"i: Lamech goes blind. Later he accompanies his son Tubal-Cain, the weapons dealer, on a hunt. He meets his grandfather Cain, mistakes him for an animal, and kills him. His son Tubal-Cain is killed as a punishment for the patricide.