בְּיָ֣ד חֲ֭זָקָה וּבִזְר֣וֹעַ נְטוּיָ֑ה כִּ֖י לְעוֹלָ֣ם חַסְדּֽוֹ׃
강한 손과 펴신 팔로 인도하여 내신 이에게 감사하라 그 인자하심이 영원함이로다
Midrash BeChiddush
בְּיָ֣ד חֲ֭זָקָה “With a strong hand...” (Ps. 136:12) This refers to the generation of Arpachshad. I did not find any Midrashim regarding his life, even though I had heard that in one book they wrote great things about him but I did not merit to find it. Therefore, I was not able to find any references to this verse. Similarly, with regard to the verse, לְגֹזֵ֣ר יַם־ס֭וּף לִגְזָרִ֑ים “Who split apart the Sea of Reeds,” (Ps. 136: 13) which refers to the generation of Shelah.