From the early stages of this story I knew that my characters must have something in common; something so strong that it can cross cultural and lingual barriers. Faith in Christ is obviously one of the things that pulls them together. I thought I was satisfied with that, but now I realize that I had never quite put my finger on it. There has to be something else that makes them best friends. There are millions of Christians in the world, but something has to make these two such kindred spirits that separation is absolutely devastating.
Before I get to what that is, let me mention that I've been reading C.S. Lewis. I found exactly what I had been looking for all along. It explains what I knew, but couldn't put into words. Leave it to C.S. Lewis to put it so beautifully.
"What I am now going to say is merely an opinion of my own without the slightest authority, which I submit to the judgment of better Christians and better scholars than myself. There have been times when I think we do not desire heaven; but more often I find myself wondering whether, in our heart of hearts, we have ever desired anything else. You may have noticed that the books you really love are bound together by a secret thread. You know very well what is the common quality that makes you love them, though you cannot put it into words: but most of your friends do not see it at all, and often wonder why, liking this, you should also like that. Again, you have stood before some landscape, which seems to embody what you have been looking for all your life; and then turned to the friend at your side who appears to be seeing what you saw--but at the first words a gulf yawns between you, and you realise that this landscape means something totally different to him, that he is pursuing an alien vision and cares nothing for the ineffable suggestion by which you are transported. Even in your hobbies, has there not always been some secret attraction which the others are curiously ignorant of--something, not to be identified with, but always on the verge of breaking through, the smell of cut wood in the workshop or the clap-clap of water against the boat's side? Are not all lifelong friendships born at the moment when at last you meet another human being who has some inkling (but faint and uncertain even in the best) of that something which you are born desiring, and which, beneath the flux of other desires in all the momentary silences between the louder passions, night and day, year by year, from childhood to old age, you are looking for, watching for, listening for? You have never had it. All the things that have ever deeply possessed your soul have been but hints of it--tantalising glimpses, promises never quite fulfilled, echoes that died away just as they caught your ear. But if it should really become manifest--if there ever came an echo that did not die away but swelled into the sound itself--you would know it. Beyond all possibility of doubt you would say 'Here at last is the thing I was made for.'"
I honestly don't know what they will have in common outside of their faith, but I hope it will make a bond that can be as beautifully felt as this passage I've just recited.