There are many types of debt a man's heart can be beholden to.
A warning is the debt of fear; it is easy to pay back with bravery. Courage bought by strength or by stupidity, and neither needs to be especially great either. Loyalty is the debt of love. But love is not steady, it waxes and wanes. And love can have competition, a man who loves his own life will rarely choose another, no matter how much love there is.
For debt to be a true stranglehold, it must stand alone, it needs no competition. Its price can never be stipulated yet it can never be given freely. It needs to be so crushing and eternal that men remember it till the end of days, yet it needs to be so gentle that man is not tied to it in any way but from within oneself. There is only one such act I have found to be as tender yet so heavy, one that leaves a wound eternal yet unseen. There are not enough coins to pay for it, nor is any labour sufficient: forgiveness.
