You are the bows from which your children As living arrows are sent forth.

这是个介词+which/whom/whose的定语从句，

from后面那句话都是用来修饰bows的，其中as

living

arrows（介词短语）修饰your

children,

are

sent

forth是个被动语态，指被朝外发出。

分为两句就是：You

are

the

bows(弓).

Your

children

as(作为)

living

arrows

are

sent

forth(朝外)

from

the

bows.

直译过来就是：你们是弓，你们的孩子作为生命之箭是从弓里被往外射出的。整合起来就是：你是弓，儿女是从你那里射出的箭。