The Bible in the book of Psalms compared children to swords in the hands of the mighty, so they are in the hands of those they are blessed with.
Mighty men use swords as weapons of war both as defence and offensive weapons so also are children in the hands of their parents. They become weapons against reproach and shame and a veritable tool to boast in the the presence of enemies and detractors; who goal are distract us from our focus on our goals in life.