TORONTO — Ariel Wyner dedicated his band’s rendition of “Do You Hear Jerusalem Moan?” to slain American-Israeli hostage Hersh Goldberg-Polin. Then he started strumming the mandolin.

Perhaps that’s why I’ve always been fascinated by Jacob’s ladder, scaled by unafraid angels, its top reaching all the way to the sky. As described at the beginning of this week’s parsha ...