In the German Psalter, it's verse 5:
was ist der Mensch, daß du seiner gedenkst,und des Menschen Kind, daß du dich seiner annimmst?
In the ESV, this is:
What is man that you are mindful of him,and the son of man that you care for him?
Structurally, "der Mensch" ("man") parallels "des Menschen Kind" ("the son of man"), but the genitive relationship shows that this "son" has a lower rank than the "man." He's under his authority and obviously younger. The two figures here continue the narrowing scope that began in verse 3: the "heavens," "the moon and the stars," "man," and finally "the son of man." This sort of zooming in emphasizes the smallness of "the son of man," and yet he still receives God's care.
