My friend was taken back because when he had read that verse in other versions it said that Jesus was "filled with compassion" not that he was indignant. This seems to be a significant shift in the atmosphere of the scene. Jesus is no longer presented as compassionate but annoyed. What is the new NIV doing?
It seems that the translators have chosen to use a less widely attested reading. While there is more textual evidence for describing Jesus as "'compassionate," some NT scholars think the description of Jesus as "angry" is more accurate. Let me explain.
In the context of the story, describing Jesus as "angry" seems to fit some of the other vocabulary. In 1:43, after Jesus has healed the leper, Jesus "upbraids" or "sternly warns" the man and then sends him away. Actually, the terminology is "drove him out" the same description of what the Spirit did to Jesus after his baptism. Thus describing Jesus as "compassionate" in 1:41 does not seem to fit with his actions in 1:43. It is easier to see an angry rather than compassionate Jesus scolding a man and driving him out.
Bruce Metzger was not so sure. In his textual commentary he notes that it is easy to understand how a scrupulous scribe might substitute the word for "compassion" in place of "anger". On the other hand, it is hard to account for someone substituting "anger" for "compassion" (p. 65). Thus anger might be the original reading. But he also points out that Jesus gets angry in Mark 3:5 and 10:14 and scribes did not find a need to change that terminology. Thus, English translations from the KJV on have described Jesus as "compassionate" here rather than "angry."
But the NIV 2010 and the CEB both are now describing Jesus as angry here. Why Jesus might have been angry is difficult to say. Perhaps he was mad that the leper questioned his willingness to heal him? Or maybe Jesus was annoyed that his preaching tour was being interrupted (1:35-39). The reason is not stated and thus may explain why, if "anger" was the original reading, it was changed by a later scribe. There is no clear explanation for why Jesus should be angry with someone seeking to be healed. But he does exhibit compassion to those who he ministers to (Mark 6:34; 8:2; 9:22).
In his commentary on Mark R. T. France suggests that Jesus was angered by the suffering that the disease and society had inflicted upon the man (p. 117). But this fails to explain why Jesus than "upbraids" the man and "drives him out" in 1:43.
Yet, this is a rather odd section of Mark. In the paragraph prior to this one Jesus goes off to pray and stays there till his disciples find him. When they tell him "everyone is looking for you" he replies, "let's go someplace else to preach" (1:38). We are accustomed to thinking Jesus wants to be found by those who seek him. But in Mark 1:38 Jesus does not want to be found and it is possible that he gets angry at those who question his willingness to heal them.
It will be interesting to see how acceptance of this reading plays out in teaching and preaching. Some NT scholars, like France, have already incorporated it into their commentaries. But what kind of a rethink will it require for us as we now encounter a Jesus who possibly gets inexplicably angry? This is not the Jesus that is often portrayed today. But it may be the Jesus of Mark's Gospel.