Barr brings up a few interesting points throughout "Modern Physics and Ancient Faith", but he never really goes anywhere with them. It's like a whole lot of introductory lectures on physics: interesting, but not nearly enough to come to any accurate conclusions about physics as a whole.
Barr's arguments are not clinically logical; rather, he prefers a hand-wavey style of explanation. This is a bit of a double-edged sword, since the arguments are designed to make you think, but they lack the airtightness of a solid proof. For instance, Barr devotes a few chapters to the idea of order and complexity, claiming that the deeper we go into the quantum world, the more orderly we find things. I have no problem with him saying that, but his proofs are a bit lacking.
A good way to summarize Barr's style of argument in this passage would be the snowflake. A snowflake exhibits high levels or symmetry (often about multiple axes), which is quite orderly. Now science will tell us that this is merely how the atoms and molecules bond together, so it's no evidence of design. Barr would likely counter this by saying that these molecules also exhibit specifically ordered traits. In fact, their constituent atoms are also highly ordered; the electrons, protons and neutrons within the atoms are equally (if not more so) ordered; and the particles like quarks that make up the electrons and such are also ordered.
Barr has shown only that order permeates the universe, whether in macro or micro/quantum scale. However, the problem is when people try to extrapolate design from the mix. Barr doesn't specifically posit design in this section (if I'm not mistaken), but it's likely the driving force of his argument. And while many will accept that the universe is ordered, is that proof enough of design? I don't think so.
Barr seems intent on reconciling science and faith, but everyone has been trying to do that for the past 20 years. Maybe it's time to accept that science doesn't speak for religion and that religion isn't science.
Overall, it's not a bad
book, but if you're looking to win an argument or convince someone to think critically, I'd recommend a book with more punch.