Commentaire sur Les Nombres 31:26

שאו את ראש means, TAKE THE CENSUS.

שא את ראש המלקוח השבי, “count the total of the spoils of beast and humans.” The word מלקוח is a reference to the animals, the word שבי is a reference to the human prisoners. The two words fit together just as the words שמש ירח, “sun (and) moon,” without the conjunctive letter ו; (compare Chabakuk 3,11).

Make an accounting. [Thusשא] means קבל ["take" or "receive"] as in לא תשא שמע שוא ["Do not receive a false report"] (Shemos 23:1). But it is not in the sense of "raising" as in ישא פרעה את ראשך ["Pharoh will lift off your head"] (Bereishis 40:19). The meaning of ראש [lit. "head"] is an accounting of the total, as in כי תשא את ראש ["when you take a census"] (Shemos 30:12). A total is termed ראש ["head"] because it is the tradition of those who are accounting takers to write the total at the head [i.e. top] of a tally sheet.