"Even Christians in Pakistan are somewhat mixed in their response," Mission Network News quoted him as saying. "There are those that are quite glad to see a return to civilian government, and there are others that are also concerned with, I think, the uncertainty of what is going to happen now for the future."
Musharraf ended his nine-year reign as Pakistan's army chief when he stepped down on Monday to avoid impeachment.
Discussions on the new president already ran into trouble on Tuesday when coalition leaders came to blows over the re-appointment of 60 judges who were purged by Musharraf last year because they opposed his election for a second presidential term.
Musharraf was a key US ally in its campaign against terrorism. Now rights groups are anxious to see whether his departure will lead to tighter controls on non-Muslim religions under the largely Islamic coalition government.
Stability took a further knock on Tuesday when a suicide bomb in the compound of a hospital in northwest Pakistan killed 20.
Penner said there was an urgent need for Christian leaders in Pakistan to "help Christians in the country know how to be good citizens at a time when Pakistan needs good citizens".
"They need people who are concerned about their country and who are going to be able to make a positive impact."
