Since it is a righteous thing with God to repay affliction to those who afflict you,
A. Our own naive simplicity is one cause of it.  When rules of health, physical laws, the nature of human beings and all of the dictates of common sense are violated with impunity, suffering may, and frequently does, follow as a result.  In short, much human sorrow and suffering are caused from ordinary stupidity.  The woman who marries "the son of Ahab" is a prime example of this.  She did not have to do it, but in spite of father's advice and mother's tears she married the town's profligate!