Thou hast declared thy strength among the people By the mighty acts of it here following. Thou hast redeemed thy people Namely, out of Egypt, after a long and hard bondage; which he here mentions to strengthen his faith in the present trouble. The sons of Jacob and Joseph The people of the Jews are very properly styled the sons of Joseph, as well as of Jacob. For as Jacob was, under God, the author of their being, so was Joseph the preserver of it. The Chaldee paraphrast appears to have understood the words thus, rendering them, The sons which Jacob begat and Joseph nourished. Joseph was indeed a kind of second father, and they might well be called his sons; without whose care, humanly speaking, there had been no such redemption, nor people to be redeemed.
Related Commentaries of Psalms 77:14
Psalms 77:14-15
14 Thou art the God that doest wonders: thou hast declared thy strength among the people.
15 Thou hast with thine arm redeemed thy people, the sons of Jacob and Joseph. Selah.