As far as i know, the Gospel is the only holy Scripture (religious text) which teaches saving grace. This is the power that actually changes people for the better. It humbles them instead of promoting religious pride which only causes more hate rather than love. You can say that many so called Christians are proud and unloving, but that is because they are either still learning and growing, or they just haven't actually received the true Gospel message into their heart.
I have observed that some people love religion, but not the Gospel. The Gospel teaches us to humble ourselves, to turn the other cheek, to love our enemies, and to bear reproach . This is difficult but its also Gods discipline that helps us actually change and learn to love. You cant love another person as yourself until you see that you yourself are a hopeless sinner. When you judge yourself instead of others, as the Gospel teaches us, then you see that you are no better than anyone else, and its becomes much easier to love everyone else. Some people say that they love people , but in reality they dont know what love is. They love people who love them, but they hate people who hate them.
The Gospel teaches us to love even those who hate us. Not that we will be perfect at loving them, but we will not hate them either because we see how fallible every person is, and we understand why they hate us. We are not perfect but we become mature in our thinking. Thats what perfection is and growth comes from that which helps us become better and better at truly loving other people, in time. This isn't accomplished merely by following a command to love our enemies, but its accomplished by obeying the Gospel as a whole. It shows us our inner self, and shows us what our enemy is like from the inside as well. It helps us to understand the people we hate just as we understand ourselves. The Gospel opens peoples eyes and lets them see things that otherwise they would never see. It is quite remarkable, and very unique. It is truly spiritual.
Matthew 5:43 “You have heard that it was said, ‘Love your neighbor[a] and hate your enemy.’ 44 But I tell you, love your enemies and pray for those who persecute you, 45 that you may be children of your Father in heaven. He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous. 46 If you love those who love you, what reward will you get? Are not even the tax collectors doing that? 47 And if you greet only your own people, what are you doing more than others? Do not even pagans do that? 48 Be perfect, therefore, as your heavenly Father is perfect.