Practicing Love
The essence of God is love, and Jesus showed us who God is. Jesus practiced love. He didn't just talk about it, he did it. He loved people, not just in feeling but in action. His harshest words were directed at religious leaders who didn't live up to what they taught people to do. When he was with people who were rejected or looked down upon by others, he was compassionate and gracious and generous. Those three words perhaps best express love - compassion, grace, and generosity. (See my book, Moral Values - http://jimmylreader.files.wordpress.com/2014/04/moral-values1.pdf.)
When our principles and policies, our beliefs, are more important than people, we are in danger of no longer following Jesus. Actions toward people that are without compassion, grace, generosity - without love - reveal hearts not connected to Jesus in that moment. Talking about love is easy; acting in love is not. This is what Jesus meant by the narrow path.