My interpretation is that the author is Christian (he says this) and he is against meditation for reasons commonly given by many Christians to discourage people from meditating
Again, this is _your_ interpretation. They only said they're Christian, and you've decided this must be the reason they're against, and their opinion is worthless. You're just colouring their opinion with YOUR preconceptions.
Their opinion matches my experience, and other commenters, and I'm not Christian at all. Why are you taking it so personally? It's an intellectually stimulating topic, you're free to disagree without dismissing the person based on their religion.