I wonder, can we love our neighbor without knowing about their 'faith'? I suspect that loving people has more to do with building an interpersonal connection rather than obtaining an 'understanding' of another's religious tradition. I think that often this kind of 'understanding' can lead to stereotyping and some 'misunderstanding' as faith is very individual and often times veers from published dogma. Of course, if your religious tradition encourages hate for those outside of your 'faith' it may be difficult to make that relational connection. Consider this passage from Luke 10 ...
25On one occasion an expert in the law stood up to test Jesus. "Teacher," he asked, "what must I do to inherit eternal life?" 26"What is written in the Law?" he replied. "How do you read it?" 27He answered: " 'Love the Lord your God with all your heart and with all your soul and with all your strength and with all your mind'[a]; and, 'Love your neighbor as yourself.'[b]" 28"You have answered correctly," Jesus replied. "Do this and you will live." 29But he wanted to justify himself, so he asked Jesus, "And who is my neighbor?" 30In reply Jesus said: "A man was going down from Jerusalem to Jericho, when he fell into the hands of robbers. They stripped him of his clothes, beat him and went away, leaving him half dead. 31A priest happened to be going down the same road, and when he saw the man, he passed by on the other side. 32So too, a Levite, when he came to the place and saw him, passed by on the other side. 33But a Samaritan, as he traveled, came where the man was; and when he saw him, he took pity on him. 34He went to him and bandaged his wounds, pouring on oil and wine. Then he put the man on his own donkey, took him to an inn and took care of him. 35The next day he took out two silver coins[c] and gave them to the innkeeper. 'Look after him,' he said, 'and when I return, I will reimburse you for any extra expense you may have.' 36"Which of these three do you think was a neighbor to the man who fell into the hands of robbers?" 37The expert in the law replied, "The one who had mercy on him." Jesus told him, "Go and do likewise."
I think that the priest and the Levite probably had a dim stereotypical religious view of Samaritans ... but the Samaritan was the one that Jesus used to teach the Jews of His day ... who also had a dim view of the Samaritans ... about loving your neighbor.
The way we judge each other is a sad commentary on modern day 'faith' ... we justify this judging with words like 'contending for the faith' and 'fruit inspection'. The way we are attracted to talking heads that find fault with other believers is a sad commentary on the church.
I have learned with experience that accepting people with other faith traditions is a very rewarding experience. Loving people who are not like me and opening up to receive love from them makes me a better person. Judging each other is poisonous ... even when it is veiled with religious words. My aim these days is to Major on the Majors ... loving God and loving people ... all of them. Now, go and do likewise :)