Bamidbar 11:29

המקנא אתה לי means, “art thou envying where I should envy”. לי — the word לי meaning the same as בשבילי, “for my sake”. Wherever an expression of the root קנא is used it implies that a person sets his heart on the matter, whether it be to take vengeance or to help; — emportement in O. F. (English = zeal) — he holds the thickest (heaviest) part of the load (i.e. he takes the responsibility for carrying out a matter).

וַיֹּ֤אמֶר לוֹ֙ מֹשֶׁ֔ה הַֽמְקַנֵּ֥א אַתָּ֖ה לִ֑י וּמִ֨י יִתֵּ֜ן כׇּל־עַ֤ם יְהֹוָה֙ נְבִיאִ֔ים כִּי־יִתֵּ֧ן יְהֹוָ֛ה אֶת־רוּח֖וֹ עֲלֵיהֶֽם׃

And Moshe said to him, Enviest thou for my sake? would that all the Lord’s people were prophets, and that the Lord would put his spirit upon them!