The reason this law still exists is because blasphemy is included in the Irish constitution and so to remove it would require a referendum which "would rightly be seen as a time wasting and expensive exercise" [1]; the law is effectively a dead letter. With this becoming popular, we'll probably get a referendum moved forward with the result being overwhelmingly in favour of removing it. The person who reported him claimed he/she was not offended[2]; it wouldn't surprise me if it was done just to highlight the silliness of the law.

[1]: https://en.wikipedia.org/wiki/Blasphemy_law_in_the_Republic_...

[2]: http://www.independent.ie/irish-news/news/garda-launch-blasp...