This quote came from a book by Randy Alcorn called, “Safely Home.” To make gold pure they put it to the fire to burn off the impurities. In 1 Corinthians 3:13 it talks about us being tested by fire (trials). This is how we should live our lives. We should strive to be so much like our Savior that we do not mind the trials and temptations because they help us see how much like Him we are and what we need to get rid of in our lives. My encouragement to you is to not fear tough times but use them to become more like our God.