אור החיים — איש אמו ואביו תיראו

Q — The verse on honoring parents opens in the singular — 'איש' (a man) — yet ends in the plural — 'תיראו' (you [plural] shall fear). Why the grammatical shift?

A — Or HaChaim reads 'תיראו' with a double meaning: both a command to revere one's parents and a description of its result. The single 'man' is commanded to fear his parents, but the outcome extends beyond him to his children, who learn to honor him in turn. He gives two mechanisms: first, that spiritual traits of holiness pass from parent to child as if by inheritance; second, the moral force of personal example — when a son sees his father honoring his own father, he absorbs the lesson (illustrated by the folk tale of the wooden bowl). Thus one act of reverence produces two — 'מצוה גוררת מצוה,' one mitzvah draws another.