Pope Shenouda III
When the rich young man asked the Lord: "Good  teacher, what good thing shall I do that I may have eternal life?",  why did the  Lord reply: "Why do you call Me good? No  one is  good but One, that is, God" (Matt. 19:16,17)?  The reply:
 The Jews were  accustomed to calling their teachers good teacher'. So  the   Lord Jesus  Christ wanted to ask the young man: "Are you giving Me  this title as a  routine custom, as you would do for other teachers? If  so, know that  no one is good but One, that is, God. And do you believe  that I am this  God?"
 The   Lord Jesus Christ did not say that He was not good but rather, on  another occasion, He said: "I am the, good  shepherd" (Jn.  10: 11), and He also said: "Which of you convicts Me of sin?" (Jn. 8:46)