In the above article, to which I might come back again in a later posting because I believe that it contains a few very valid points, the author makes a claim about buddhist meditation: namely, that it is a highly unreliable tool and can even "exacerbate depression, anxiety, and other negative emotions in certain people."
Now, I certainly think that this can be the case; most books and articles I read on the subject admit that there can be issues, and that people with severe mental problems should probably stay away from meditation. They then move on to state that those cases are extremely rare.
In my personal life, meditation has had a tremendously positive impact, so I cannot attest to anything else. But I sure understand, on an emotional as well as intellectual level, how feelings of losing one's self, of "unreality", might put some people in a lot of dismay. Personally, I always fancied meditation to be a rather safe method, for the simple reason that you have to put in quite a lot of time, that you have to practice on a very regular basis for an extended period, in order to actually achieve anything. It has its own safeguard built right into its core, so to speak.
But that is not entirely true.
The more I think of it, the more I conclude that meditation is not one thing, but many different things.
If you sit down to meditate, regardless of the method you employ, there will always be thoughts passing through your head. And some of those thoughts will be about the meditation you're just having. In other words, you do interpret your meditation while you meditate. In all practices I know, the goal is letting go of exactly those interpretations - but since this is basically a life-long journey, those thoughts, those interpretations, will be with you for quite a while. And, since you cannot easily have a clean cut between your thoughts and "what meditation really is", that wordless state, your thoughts are actually a part of your meditation. Your words shape your experience of wordlessness. And those words, of course, are themselves informed by your religion, ideology, worldview - especially if your meditation is an integral part of your religion.
If you sit down thinking that you're now enjoying the presence of Jesus, this is a whole different experience than if you sit down with the assumption that you slowly realize that your self is an illusion, which will eventually lead you to enlightenment.
So I posit that christian meditation is not just meditation with some added christian flavor, but a completely different affair than buddhist meditation. The same goes for every other "type" of meditation out there. They are all wildly different affairs.
And of course, this also implies that some of those interpretations are more wholesome than others. I guess that the types of meditation that get practiced in destructive cults tend to be of the not-quite-so-wholesome kind. A meditation engulfed in pressure and idolization of a leader... nah. Can't be all that good.
So, it's never really "just sitting". I think this is something to be aware of when you start a meditative practice.