What is the yoke?
Ibn Ezra: It is Musar.
Palgei Mayim: It is the yoke of Torah and Mitzvos.
Should he bear a yoke only in his youth?!
Rav Sadya Gaon: It means from his youth. Ri Kara, Rid - if he did so, he will succeed when he gets older. Happy is one who already paid his loan documents. Even though he is sad now, he is happy later. Happy are Yisrael, who already received a decree for all their sins. Woe to the nations, who later will be stricken for all their sins. "Tam Avonech Bas Tziyon Lo Yosif Lehaglosech Pakad Avonech Bas Edom Gilah Al Chatosayich" (4:22).
Ibn Ezra: Perhaps the author said so because he was a youth when he was captured, or to strengthen the hearts of the youths.
Palgei Mayim: Also this refers to "Tov Hashem l'Kovav" (25). He is good also to one who bears the yoke of Torah and Mitzvos in his youth, from when the Yetzer ha'Ra is aroused to come out, for then it has no power to make him sin.
