In Doctrine and Covenants section 122 verse 7, Heavenly Father gives him an answer to this question, "And if thou shouldst be cast into the pit, or into the hands of murderers, and the sentence of death passed upon thee; if thou be cast into the deep; if the billowing surge conspire against thee; if fierce winds become thine enemy; if the heavens gather blackness, and all the elements combine to hedge up the way; and above all, if the very jaws of hell shall gape open the mouth wide after thee, know thou, my son, that all these things shall give thee experience, and shall be for thy good."
God gives us each our own trials that we must go through during this mortal life to help us grow and become better people. I have seen in my own life how the most difficult times for me are the times that I learn the most.
Paul V. Johnson of the First Quorum of the Seventy gave an excellent talk on this subject during the April 2011 General Conference entitled: More Than Counqereors through Him That Loved Us. In his talk he reads a quote from an apostle that I really enjoyed and think sums up this subject quite well, it says, “No pain that we suffer, no trial that we experience is wasted. … All that we suffer and all that we endure, especially when we endure it patiently, builds up our characters, purifies our hearts, expands our souls, and makes us more tender and charitable. … It is through sorrow and suffering, toil and tribulation, that we gain the education that we come here to acquire.”
