“There is no one like the God of Jeshurun, who rides across the heavens to help you and on the clouds in his majesty. (Dt. 33:26)
As Tara-Leigh pointed out, the name Jeshurun is used three times in the Song of Moses (Dt. 32-33) and only one other place in Scripture. Jeshurun means “Upright one,” and it feels out of place when describing Israel, because Israel has been anything but upright.
But here’s the thing. Jeshurun, according to gotquestions.org, can also be translated “Beloved One.” In the Septuagint, the Greek translation of the Old Testament, the word is rendered ἠγαπημένος (Agapemenos). Agape is the unconditional love of Christ poured out on us.
The only other place Jeshurun is used outside of Deut. 32-33 is Isaiah 44:1-2:
“But now listen, Jacob, my servant, Israel, whom I have chosen. This is what the Lord says— he who made you, who formed you in the womb, and who will help you: Do not be afraid, Jacob, my servant, Jeshurun, whom I have chosen.”
So if Jeshurun is “Upright One,” then it does feel ironic when applied to Israel. Because upright describes human behavior, and, well, Israel has behaved very badly at this point.
But if Jeshurun is “Beloved One” then it is more about God’s attitude toward us, and not our behavior toward God. We are beloved by God in spite of our behavior, not because of it. Israel is the agapemenos—the Beloved One, because God formed her. He chose her.
I am Jeshurun! Left to myself, I am so far from upright. But God has pronounced me upright. I am so much less than lovely, God’s heart toward me is only love. Oh my God, I praise you for singing over me!