I have always found the humility of Muslims saying "In sha'Allah" admirable. It's a beautiful way to remind ourselves that our fate -- and our life -- is not entirely in our hands.
In America I sometimes hear a similar saying of "Lord willing" which is a shortening of a verse from James: "If the Lord wills, we shall live and do this or that."
In parts of the UK the equivalent is 'if we're spared'. Some people may decide this means that the person saying it is probably a miserable old codger, the sort of person who says "mustn't grumble" when asked "How's things?"
