The problem is that we want to be right instead of letting our lights shine. Being right means to be drawn into debates and arguments with people who wrongly criticize us. It can lead us to discouragement and neglect on the path that God has us on. When we argue and retaliate with those who subtly and covertly attack us we are basically agreeing with them.
Letting our lights shine means to overlook the negative criticism and oppression of others and to respond kindly. It means to keep doing what we're doing and to stay in the center of the path that God has us on. We are to keep pressing on and to not look to the right hand or the left. This means to not get involved with defending ourselves and repaying evil for evil by cutting others down in like kind.
You know what that statement says, The greatest revenge is massive success!" We shouldn't be focused on revenge at all because that belongs to God. That quote is simply a soothing balm and positive motivation to not waste time and energy debating and retaliating. We need to keep to the mission or business that God has given each of us. Being the light means to respond to attempts to stop us with Godly grace, prompted by the Holy Spirit and to keep moving forward and looking ahead. Who cares about being right when there are so many benefits to being a light?