"I often hear people say, “I don’t need religion to be a good person,” but rarely does anyone consider the question, “What does it mean to be a good person?” Usually the response to that question is, “I’ve never killed anyone; I don’t steal.” Well, that does not define a good person; it merely describes someone who is not extraordinarily bad. Furthermore, there are saints who have committed those sins, and not only did they not remain wicked, they became holy. So, for Christianity, to be good does not mean never to have done bad things. Rather, it means to come into union with God through repentance." (Archimandrite Vassilios Papavassiliou)
“Some people ask ‘Why is being a good person not enough to get you into heaven?’ Jesus Himself gave the answer in the Gospels when He pointed out the flaw in this question. He said ‘No one is good but One, that is, God. No one is a truly, or perhaps better said, fully a “good” person, meaning that no one is completely and thoroughly good without a drop of sin but God. That is why, no matter how virtuous we are, we need to have union with God and accept His grace in humility.” (S. Michael Houdmann)
“If we are not God-centered it is too easy to delude ourselves with feel-good experiences and actually think we are a “good person” when in fact we are still self-centered. We are fragmented in ourselves and with other people if God is not our highest love.” (Sacramental Living)
“[On being a “good person”] For example, if the good of our family, not God, is our highest ideal, we may think ourselves as being loving and doing right because we are taking care of our own properly, but this is not enough. If our family, and not God, is our center, we will tend to care less for other families. We may feel good that we work hard and sacrifice so our children go to good schools, live in a good neighborhood, eat well and go to a good church, but God calls us to do more and share our money, time and talents with those who are less fortunate. We tend to do this more or less in direct proportion to where God is in our lives.” (Pastor Timothy Keller)
“The true standard of good for the Christian is Christ and we believe that a sincere life in His Church and through His grace results in a transformation in which we assume more and more of His goodness and think and act accordingly. We believe that sheer force of will, or sheer human will power, can never result in a being a truly good person. This is because the standard of good is a God who is without sin, that is, without any area where He falls short, and we do not have it in us to achieve this without joining ourselves to Him.” (Sacramental Living)