If I had to guess, and since I have no context at all for this video that is exactly what I am doing, I would say that Keller here is talking directly to Christians. It’s just a hunch, but this is one seriously powerful 1 minute and 38 seconds. And it is quite a knife to the heart too. The irony is, I think, that not only do Christians have a habit of committing these ‘crime,’ as it were, against people who are ‘not like us,’ but we have a terribly bad habit of committing them against one another too. A quick scan of the church of blog will demonstrate this rather easily. This packs a punch so be prepared.
Soli Deo Gloria!