I don't think I've ever explained my comments and spam policy here at Lfab. Now may be a good time, since I got an interesting spam comment on yesterday's post.
The cardinal rule is to make sure that your comment is relevant to the post at hand. I don't appreciate it if you come in on some generic search term (like "atheism" or topless beach -- I get a lot of spam on that one, mostly ads for viagra and Russian ladies who want to date you), and then copy/paste verbatim exactly the same thing you've posted to a hundred other blogs using the same query word. If you've arrived on a generic query, please feel free to leave a comment, linking back to your own site/article if you like (even if you're selling something on your site), as long as it's clear from your comment that you read the post at hand and you're responding to it or responding to other comments on the post. If your comment contributes to the discussion, then relevant links are fine. (Highly non-relevant and/or phishing links are obviously a no-no, though.)
Additionally, please do not copy/paste an entire multi-page article into the comments of my blog. If my post inspires you to write more than six or seven paragraphs of response, that's fantastic, but consider writing a response post on your own blog and linking to it.
Also, I generally don't delete trolling or other uncivil comments here (since I get so few, they're not a problem), but I do ask everyone here to keep your comments civil and respectful of other commenters. I'd like this to be a space where people from a variety of different viewpoints can have a constructive exchange of ideas, and that requires a little bit of basic courtesy.
Now I'm not going to delete the spam comment that inspired this since it was on a link-dump post, hence there's no discussion to derail. It starts with a highly original warning: just because Bible-based predictions of the second coming of Jesus have been wrong for 2000 years, that's no reason to doubt the Bible's awesome predictive powers. The Bible says there will be natural and man-made disasters, and there have been. See? Thanks Bible!
But seriously, if you choose to respond to our friendly neighborhood Armageddon-predictor, please remember the above rule about civility (as some regular commenters who already know the drill have done). Thanks!